What about the max. size of the module, and in which format it is going to be?
.it/mptmp, there are a few things I need to look up with OpenMPT but honestly (unless information is lost) I might just convert it between .it & .xm since technically I'm a MilkyTracker composer which only works with xm. Eventually I want to dump it altogether.
Max file size isn't too much of a concern but let's add no more than 8mb. Multisampled instruments (I've a lot of that) can take up a bit of room if you're not careful.
The size that you'll get is max. ex. My modules size may reach ~6-10mb.
I use only .it or .mptm (with VST that works only in mpt, I prefer simple reverb like Ambience or Freeverb, not VSTi). Other tracker formats are useless. Limiting yourself in features is absurd. You should realise that we are living in 2016.
I've seen enough such challenges, it's better to compose quality and interesting music.
Unless you wanna do a 3-way personally I'm going with Alchemy
. Understand where you're coming from but a number of your comments feel somewhat directed at me
A string quartet only has 4 players, if they don't play more than one string at a time that might as well equate to 4 channels. Being an enthusiast for 1990s video game music it's also another "feelsbadman" kinda thing too. A lot of those composers did transition into the modern "just make music" era but brilliant ones like David Wise couldn't always do that. Personally working with 8-channels has helped me a lot, particularly with melodic constructs.
Long story short: I think you should look for another partner. As a collab I'm not expecting it to be the next best thing to sliced bread however your opinions seem to contradict the very reason I got into music tracking xD. That might also mean your skill level is much higher as well.