I didn't think I'd ever want more than 144hp - until I did... took about 6 months to get to that point and now I have about 1200hp - but saying that I may have stopped at 208hp if I'd bought a bigger case to start with (mantises were not available at the time)

As a 40 year old who didn't upgrade live 8 until this year, still works with mostly digital synths from the early 00s, and rarely if ever sells/trades/upgrades gear... I really don't feel I have an issue. I'm not interested in collecting and I've learned that shiny new lights are only shiny for a week. With that said, there are bound to be moments of GAS in my future, but only minimally modular GAS. Famous last words... I know.

odd-pairings are probably a good idea and overlap is no bad thing

Good tip.

if you want to stay at this point - stop coming to modulargrid, don't go to any other modular forums, don't go to any shops either online of in real life - don't communicate with other modular synthesists - these are all sources of gas

Lol. That's sorta the idea yeah. I am not a community guy, per se. Wonderful community. But wouldn't want to be a part of any club that would have me. Plus, staring at a forum/blogs/videos is just not what I do, really. I prefer to spend my time in front of a computer either at work, or making music.

I'd want a lot more utilities - they make everything else go both further and different - probably another 100hp or so of them for that many voices - balanced rack = 30% utilties, 20% modulation sources - other 50% = sequencers, filters and vcos

Thanks that's a good equation to go by. I still have a NiftyCase hanging around, so I may try my hand at building some utilities once I'm done with my current projects and see how well they jive with the system then consider what they could replace in the main case. But my intention is to stay with this case and only ever add-by-subtracting-first, to allude back to your first point.

Thanks for taking the time to provide feedback. Greatly appreciated!