Actually, one thing I would suggest is that you use the extra space to get rid of the 2hp modules. They're great in smaller builds, but if you're adding another 2 x 104 here, it's high time you made those functions easier to use by going with modules that are easier to work with. For example, you're considering more ADSR envelope gens...you could remove the 2hp one in favor of something like a couple of Doepfer A-140-2s, and that would up your ADSR count by three while only consuming 14 more hp. Also, the tile row could probably use another Quadratt...or perhaps a couple of Duatts...since there's a shortage of attenuators and polarizers. You could also go with a second Plaits (or a smaller 3rd party version) so you can have some nice, fat detuned sounds rather than just one single oscillator.
I should note, also, that the ochd has all of its LFOs ganged to one rate control. A better solution might be 4ms's QPLFO, which gives four independent LFOs with tap timing...and rates that can range from midrange audio all the way down to over an hour. That sort of slow rate is great for VCFs, lets the timbral results shift imperceptably over time.
Oh, and even though there's an FX Aid in there (good call), you might consider Intellijel's MultiFX tile as well...the chorusing would be useful for "stereoizing" signals, since it can take a mono input but gives you a stereo pair out.
This isn't a bad strategy at all, just be very careful to make sure there's ample space for utility-type modules.