Thank all for the suggestions. I've been using a larger setup for the past couple of years, so trying to squeeze into a smaller space is pretty foreign to me.
It seems like any kind of decent sequencing is going to need a good chunk of real estate. Like I mentioned in my first post, I have considered getting a keystep pro to handle those duties (though that would make it a little harder to use the rack as a laptop). I forgot about O_C (for a bigger rack I prefer discrete modules, but when pressed for space it's a good compromise).
I'm also now thinking about just going with the mantis case. That way I wouldn't need an external sequencer. In my "desktop" rack I have a nerdseq (for when I want to sequence a composition) and an usta (for experimenting). If I go with the mantis, I can move the usta to it and still have a respectable amount of room for other modules. The only trick with mantis is the power zones and remembering that the -12V rail provides less current than the +12.
I think I need to do an exercise with my main rack where I only let myself use a small subset of modules and see where I come up short.
Well, I have some thinking to do. Thanks, again!