the way in rack drums are tossed out as unreasonable is silly to me as the entire point of modular is to build the instrument you want to build.
-- xnax

I totally agree @xnax. It's YOUR instrument. Build what you want and re-sell the parts that aren't working for you.
Personally, I've taken a hybrid approach with drums, incorporating a desktop 808 clone with modular drums. In fact, I've dedicated 104hp just to modular drums (not including various trigger sequencers and switches) and I couldn't be happier. I may even pick up a DFAM again just so I can (*gasp) take it out of its own dedicated case and put it in my rack, because THAT'S WHERE IT WILL GET USED THE MOST. All of these "rules of thumb" for building a rack need to be taken with a grain of salt. If you want a drum rack, build a drum rack. If you want to rack up a bunch of semi-modulars together, do that. It might cost a little more than alternative methods, but that's on each of us to weigh the costs and benefits. If I listened to every piece of advice given on this forum, I'd have ended up with a bunch of stuff that's great for generative ambient or West Coast-ish Buchla bongo sounds but useless for what I actually find myself doing most of the time.
Only you know how you will make the best use of your gear. Experiment and have fun.