Interesting build...in a very real sense, you've managed to come up with the modular synth equivalent of a Roach Motel: patches go in, and sounds can't get out.
Jim is spot-on with the point that you need to go with a bigger case. For one thing, if you're playing the guitar and realize that you need a tweak, the LAST thing you want is a super-tight interface, with little modules, knobs, and tight real estate. Remember, that thing is going to be festooned with patch cables when you're using it, so you want BIG modules, with BIG primary knobs (like your VCF cutoff) so that you can make tweaks while still maintaining optimal control of your axe. Case in point: http://www.effectsdatabase.com/model/ems/synthi/hifli That is the very coveted EMS Synthi Hi-Fli, made by the same people who gave us the VCS3 and Synthi A, and most famously used on Pink Floyd's "Dark Side of the Moon". Now, while this is something used as a guitar effect, you'll notice that the EMS designers made sure that there was ample room to grab the right control by a guitarist that would be far busier on the strings. Your build needs to be closer to THESE ergonomics, and not like the initial build above.
And as for "generative"...I'm still boggled by users who feel that they can do a tiny 3U build and still think it's capable of doing the amount of self-regulation that, well...https://modularsynthesis.com/moog/cems/cems.htm Now that there is a REAL generative system in MU format, assembled by Joel Chadabe and Dr. Bob back in the 1970s at SUNY Albany. It's a bit...um...LARGER. And even if you shrink this down to Eurorack size and make ample use of multifunctional modules, it's STILL going to be larger. You're missing loads of things needed for this: comparators, logic, CVable function gens, discriminators, etc etc...in short, all of the self-regulatory functions that make generative generative. I'm even inclined to think that Jim's suggestion of 2 x 104 is too small to really get this right, especially if you get the ergonomics nailed.
I'd suggest spending some time studying MG builds done by experienced synthesists/builders that use generative/stochastic principles, for starters. Second, if you don't have a copy of VCV Rack, get one, as it'll give you a lot of insight into what's necessary to get that sort of build to work. Toss this build, then come back to attempting one AFTER you've sorted out what this will actually entail.