Hi.
I'll duplicate my new stance and argument on this issue below, edited for clarity and brevity:
The filesize limit is still too small. Even after the bump it received:
https://battleofthebits.com/academy/GroupThread/11893/

Consider for a moment the function of a filesize limit in every other format. It's not supposed to be easy to hit. Consider for a minute the amount of times your samples get to 8 MB in s3xmod, or 1024 KB in nsf-plus, or even 1MB in midi. The function of the upload limit isn't that of an additional limitation; it's a measure to make sure you're not completely breaking things. NES games didn't often have 1024 KB to work with. If they had that much, they were pushing the limits. You don't need 8MB to store quality samples and you don't need 1MB to theoretically make a good midi. The Amiga is capable of more, especially in the later models. And as it currently stands, it is absolutely a bottleneck and a pain to work with. You can't always get good quality out of 256 KB (especially with the already harsh frequency limitations!) An arbitrary filesize limit that can absolutely get in the way of your ability to do stuff with those already harsh limitations. I'm not asking for more channels. I'm not asking to use higher frequencies. I'm not asking to use full stereo. We have S3XMODIT after all. No, I'm just asking for a more fair filesize limit.

AmigaMOD needs a new format. I previously conveyed to puke7 (the 7 is now a salute whenever I say it) the fact that the Amiga has multiple models. The current AmigaMOD format is based on the A500's chip RAM limit according to this forum post discussing the upgrade from 64 KB to 256 KB: https://battleofthebits.com/academy/GroupThread/11893/
It's fine for most modules, but it can be a pain if you're working with larger samples.
I propose we create a new Amiga format for the later 1990 model known as the A3000, which had 2 MB of Chip RAM out of the box. 2MB is more than enough to take advantadge of the full 880 KB floppy drive space on the Amiga. In that space, we could even include the additional channel mode (up to 32 with hardware mixing) available in the MOD format.
Additionally, the 64 KB limit could be an Amiga-Classic format for the A1000, or the first Amiga model, which only had 256 KB of RAM, and if you include the RAM ProTracker uses, it's probably about that much left.
So to review, I'm suggesting 3 formats:
1. Amiga-Classic (64KB and 4 channels)
2. Amiga (the current AmigaMOD format)
3. Amiga-Expanded (880 KB with the extended channel limits)
Alternatively, we can upgrade the current Amiga limit to 440 KB (one side of an Amiga floppy) to put it in line with other format upload limits (see post #4).

+1 all amiga format for anything can work on amiga module and executable: octamed, digibooster pro, the ultimate sound tracker custom sound engine

don't forget that s3xmodit format also accepts .mod format, whatever is M.K., from the good old The Ultimate Soundtracker, as those with 8 channels, and so on... :) - btw, i'm curious about octamed and other amiga tracker formats as well

(i can't remember, didn't Amiga 3000 and 4000 supported 1760kb floppies? i think i remember they could read high-density macintosh floppies when running system 7.x on emulation)

yeah, i've debated whether we should just bump the limit on the current format a little more rather than splitting the format. I think 440 is a little more fair for larger modules, that way we're not overcomplicating things or stepping into s3xmod territory...
You also have to consider that the upload limit on s3xmod (and many other formats) is supposed to be a "realistic-ish" limitation. It's not meant to be a hard "this is what the program could run" kind of thing, more like a suggestion. You don't frequently hit the limit in s3xmod, or nsf-expanded, or any of the other numerous format upload limits, but I do feel as though you can creep close to 256 KB very easily on AmigaMOD as it currently stands.

limits are fun, amigamod with 256k is cool (especially compared to 64 where it formerly was). for everything else, you can use sexmodit or wildchip. just my opinion, i dont rly mind any changes if they happen

I just did further research on the MOD format and it turns out that you can get the samples on a MOD file up to 128 KB each. This means that protracker modules, on hardware, can go up to around 4 MB (128*31) or so. With the correct Chip RAM installed, this is totally playable on an Amiga. Now, obviously, that's way too much for the purposes of this format; but it proves that 256 KB is a very harsh limit compared to the actual capabilities of a 4-Channel MOD file. I say we bump it up to 880 KB so that if someone wanted to use that much space, they could.
https://www.ocf.berkeley.edu/~eek/index.html/tiny_examples/ptmod/ap12.html

I think it's worth paying closer attention to the difference between file formats and hardware capabilities. Being able to store 4 MB of samples in a module does not mean that you can play that file on an Amiga. (This goes the other way as well: The audio hardware on Amiga has more capabilities than can be encoded in a module.) The question is what the goal of the "amigamod" category is.

- If it's supposed to be representative of the Amiga music scene in its golden age, the size limit of 256 kB is slightly low, but not far off the mark. The prevalence of the Amiga 500 ensured that most modules would fit within what was left of its 512 kB chip memory after the tracker was loaded. Here's an example that pushes the limit: http://janeway.exotica.org.uk/release.php?id=58387

- If the goal is to push the Amiga's hardware capabilities to the limit, the category shouldn't be restricted to the module file format, and would have to be more specific about Amiga models.

- I don't think the goal is to push the module file format to the limit, because then it doesn't make sense to restrict the category to Amiga hardware, and that's already covered by the "s3xmodit" category.

@02FD i don't know if you can store a 880kb file in a 880kb floppy, since you have there the filesystem directory information, like in all storage filesystem formats

thank you for your responses.
@nitrofurano:
I guess I kinda considered that: the amiga doesn't have any standard "requirements" for its floppies. You can go entirely proprietary and the Amiga will still read it. Explained here: https://en.wikipedia.org/wiki/Floppy_disk_variants#Commodore_Amiga
This means that theoretically, if everything were to be handled hardware-side, you could store in the full 880KB-- but this is probably unrealistic, and I don't know how possible it is given my inexperience with floppy drives. Additionally, it might eat RAM to load it anyway. So you're probably right on that.
@absence
There is no TL;DR. Please do me a favor and read the whole thing! :)

You're absolutely right. If we look at the filesize this way.
Consider for a moment the function of a filesize limit in every other format. I don't think it supposed to be something that's so easy to hit if the hardware is theoretically capable of more. Consider for a minute the frequency at which your samples get to 8 MB in s3xmod, or 1024 KB in nsf-expanded, or even 1MB in midi. The function of the upload limit isn't an additional limitation in itself; it's a measure to make sure you're not completely breaking things. NES games didn't often have 1024 KB to work with. If they had that much, they were pushing the limits. You don't need 8MB to store quality samples and you don't need 1MB to theoretically make a good midi. I don't think the filesize limit should dictate the type of module you create if the format (as in, 1 amiga format) is capable of more. And as it currently stands, it is absolutely a bottleneck and a pain to work with. You can't get good quality out of 256 KB (especially with the already harsh frequency limitations!) And I don't see why we're working with the "golden age" of Amiga, anyway. "Golden age" is a stretch; the Amiga flopped on launch, barely had a "golden age" and then went into demoscene retirement. It's not fair to look at it that way because the Amiga wasn't really ever in a golden age. It was a niche from the start, and I think the best thing we can do is ignore the particular model number and select a more feasible limit for the demoscene today. If you want to work with 256 KB, by all means, do so. But I don't see why people have to stick to that if they want to work with the other limitations of the console; an arbitrary filesize limit that can absolutely get in the way of your ability to do stuff with those already harsh limitations isn't in the spirit of this format.
EDIT:
Forgot to add: the Amiga isn't the only case of the MOD format being used; tons of other trackers use it on other hardware. You can use more than 4 channels, break the Amiga frequency limitations, and have full stereo in the final version of the MOD format. I don't think we should look at MOD as being "Amiga-feature exclusive" in the s3xmod format. And, the MOD format was totally playable with higher quality samples without breaking frequency limitations or adding channels; it was just a matter of RAM.

all the other limitations of amigamod are more annoying to work with than the filesize limit, filesize limit is easy.

Yes, but just because it's easy doesn't make it necessary. There shouldn't be anything stopping me or anyone else from going the extra mile. And in that sense, why add more limitations if all the other ones are so hard to avoid? I think 880 KB is far better for an already uniquely challenging format.

Setting the limit to 512k is totally reasonable, and I wouldn't be against 1024k, although ultimately, I don't ever actually remember the file size limit ever really coming up. It might have been an issue like once with 64k, which was definitely too low, especially with the .MOD format's complete lack of packing.

An entirely unscientific glance at .MOD format files on ModArchive indicates that a typical .MOD is around 100-200k, and the size of .MOD files on my computer indicates that to be pretty typical.

As for outliers, the largest .MOD files I have are a pair of 8-channel ones from the DoDonPachi Daioujou soundtrack, coming in at 446kB and 601kB -- the hardware the game runs on uses an 8-channel sampler chip and the devkit apparently converts .MOD files (in fact, some of the games on the PGM hardware outright steal real Amiga .MOD music lol); I'm not sure if these are the actual source files
https://modarchive.org/index.php?request=search&query=ddp_daioujou&submit=Find&search_type=filename_or_songtitle

I also have a 4-channel version of Dispyz's Datarunner on my computer, which was intended for the Amiga game Tracker Hero, and it's 360kB, so I think that's a pretty good baseline for something you'd play on an Amiga.

I can do you one better, null:
https://modarchive.org/index.php?request=view_by_moduleid&query=194942
Nearly 871KB. 4 channels. Infinite Awesome
...granted, this is a modarchive one...
That said, I think 880KB is the actual size of an Amiga floppy, it seems the hardware handles the formatting, not the disk itself. I still say that's perfectly reasonable for a hard maximum.
https://en.wikipedia.org/wiki/Amiga_Disk_File

That 871kb mod is heavily unoptimised imo. Making loops smaller and cutting the start of those pads (which doesn't make a difference to the listening experience as they use volume commands anyway) gets it down to at least 717kb in my quick gander. Also the sound effects and some drums could be looped, considering after a certain threshold 8-bit samples just become noise anyway... I'd say if you tried harder you could get it sub 600kb without making it sound bad, because of how much unnecessary tail is on those?

My proposal is a test with an un-expanded A500 (512kb ram, the most common 'base-spec' Amiga IMO), a hard drive with AmigaOS and Protracker. See how much free ram is left and then see how much you can use without causing any issues.

I'm personally fine with 256k as an Amiga enthusiast! It doesn't matter to me if it changes. I'd say the only time I've seen it as a massive issue is with an OHB, submitting bang on time only to find out you need to shed the samples and then being late. But then if we increase the limit, isn't that just gonna happen again with big samplepacks? :D/

(also I agree with Oli that extra Amiga-compatible formats could be its own cool format, but I understand it's not a priority at all)

@02FD The operating system can only read formatted floppies. That 871 kB module doesn't fit unless you compress it. The golden age I referred to was in Europe, where the Amiga 500 was very successful. I understand the situation was different in the USA.