As you can see from the responses here, everyone has a bit different criteria. It can depend on your workflow.
I’ve got two cases, a 104x9 and a 104x6. I generally don’t use them together. One I see as my “studio case” and one is my “travel case.”
But here’s what happens. I get an idea of something to try with a certain combination of modules, and then I rearrange one of the cases (usually, the travel case) into a configuration designed to take advantage of the particular idea I’ve got. I’ll then leave the patch up for several days while it evolves and I try different stuff, until I figure it’s got enough going for it that it’s worth recording. I may record a couple of sessions with the patch, if I’m still tweaking it and it’s getting better. At some point, I’ve got enough recordings of it that I’m happy enough with that I’ll figure it’s time for another reconfiguration for a new idea.
In the meantime, sometimes I need a break from the patch I’m working on, so I’ll use my second case and configure something new there, leaving my first case with the in-process patch.
Consequently, there’s a few modules that I’ve got more than one of, because I always want one in both cases-- Pamela’s, mixer, disting, ornament & crime, Radio Music, etc.
That’s working fine for me, because I’m not trying to use every module I’ve got all at once, I can have multiple in-process and different projects going on simultaneously. At this point, I’ve got enough modules without corresponding case space, that I’m figuring I’ll buy a third case (probably another travel case) just to put them all in-- can’t let a module sit outside of a case for too long, eh?
But I do have a few modules I’ll sell off at some point, and there’s a few modules still on my want list…
I suppose if I had an idea that needed multiple-cases worth of modules, I could do that with some long patch cables, but that’s not how it’s worked for me, so far.
Another approach could be to devote one case to percussion, and another to melody or something like that-- it’s occurred to me but I haven’t tried that yet-- may do so at some point.
What I did decide, is sliding-nuts are, well, nuts. With the extent that I’m constantly reconfiguring things, sliding nuts are just to fiddly. And I’ve never had anything strip out the threads.