@Jim, thanks for the ideas! Lots of points you raised, I'll try to respond to the major ones below:
-- The Jolin LPG bank you mentioned is likely a great fit here.
-- "Mixing really needs to be addressed..." Agreed! Working backwards, ES8+6 give me 10 outs to DAW, I don't see myself needing more than that with this setup. Lots of potential ways to manage the up to 10 voices, let's say main options are 4 mono + 3 stereo pairs, or 6 mono + 2 stereo pairs. I have some spare Doepfer A-138N (4-ch narrow mixer) I could slot in, those can cover some mono needs. I'm inclined to get 1 Intellijel Mixup, which seems like a low $ and HP way to up the mix channel count, and a 2nd Mixup (if needed) could later be added and chained to the first. Also, SoundStage is a new module for me, I need some more soak time to get a sense of how I'll likely use it... I'm inclined to run a LOT of my pitched sources through it and treat it like a stereo sound-field out. Net net, my current sense is another 10-16HP devoted to mixing could really meet the needs for this setup.

quite possibly!

-- you mentioned CV mixing. On that end I've got Sum&Diff, SISM, and Morph4. Do you have a more preferred setup for CV mixing / mangling? I did see your suggestion of a matrix mixer, just wondering if there's anything more / less to your preferred CV mix setup?

good start, but I find matrix mixers to be incredibly useful for cv - take copies of n modulation sources and get n different, but related and more complex ones out - I have 2 in my system that's about 1200hp for audio at the moment - they're of the smaller 10hp variety (& diy) personally if I were going to buy again (add on more likely than upgrade) I'd go for either the doepfer (bigger and better ergonomics) and/or the 4ms vcam (cv controllable) and/or one of the nlc offerings (cluster/clump - again better ergonomics and/or cv control)

-- "low priority modules" and remaining space. As of today, I've got 95%+ of the modules above (most being re-racked from earlier cases into the new case). AND there's some fluidity between this setup and my home setup. My home setup has all its major functional needs covered, and some HP to spare, so if I want to pull a few items out of the travel rig (above) and slot them into the home rig, that works fine. BUT I think where we're netting out is I'll probably need to free up 16-26HP in the rig above for LPG and mixing additions. In my next few sessions with the setup, I'll focus on (top) rows 1-3 to check which of those modules I least need in this setup.

yeah I think that's where I'd be looking too... I'd much rather have fewer sound sources and be able to route them more places and effect them more than be sound source heavy... remember you can mult outputs to different filters/effects and the fx aid has pitch and frequency shifters etc so I'd probably throw one of those in too - probably instead of scales - not sure how much use you'd get especially as you seem to have a 'battleship' sequencer with the vector and expander - with pitch already quantized

-- likely next steps: add Jolin LPGs and a little more mixing capability, and get a bunch more soak time with the setup before other changes (if needed).

sounds like a plan...

have fun!

"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia

Utility modules are the dull polish that makes the shiny modules actually shine!!!

sound sources < sound modifiers < modulation sources < utilities