Yeah, this won't be any fun to work with. This build has loads of sources, modulators...but NO submixers, only two VCAs, very little in the way of other utilities/control devices, no proper EGs, and the like. Sexy Module Syndrome in overdrive.
Since the focus here seems to be in sound generation/modification, start being hypercritical about everything that's NOT that. You need to ask yourself if any of these things can be made smaller, or...probably more sensibly...whether they even need to be there in the first place. For example, why a double sample and hold? Would a simpler module make more sense here? Why use a CFM rectifier instead of a proper waveshaper? Do those sequential devices really belong in here? Why do you need a contact mic and not an audio input module? And so on...
Another suggestion prior to this, also...increase the size of the cab to much more than you think will work, THEN add all of the necessary utilities, VCAs, etc etc...and once that's done, start paring the whole mess back while maintaining the functionality. That's not easy, but it's a good way to proceed; you're likely to find that trying to do all of what you want in this small of a cab is NOT going to work, even after trying to remove all of the extra "fat".
Also, think simpler. This looks like there's so much going on in a tight space that working with the build will actually wind up being more difficult than you might realize; remember, what you see here will be dripping with patchcables when it's in use, and that obscures the already-tight control and marking layout. Again, this runs into the possibility of having to go to a bigger cab...but trading off size for playability is always worthwhile in the long run.