There ya go! This isn't a bad build at all. The only thing that seems to need changing...and you have the space once you pull the HN mixer and the 2 hp blank...is that HN mixer. Instead of that, drop in a Doepfer A-138s. It has ACTUAL pan controls, instead of using the L+R jacks as "psuedo-pans". And you've got four VCAs prior to it, so level control to the stereo mixer will be possible. Put the FX Aid XL after that, then use its wet/dry control to add your effects to the final mix.
Smart stuff going on in here, though...the Octasource addition is spot-on, and the addition of ADDAC's Marble Physics is a huge generative plus. And the VCA complement is pretty much THERE...four up for audio, six down for modulation. The lower row might benefit from some attenuverters to invert things such as envelope signals, and there I'd suggest pulling the two 2 hp blanks and putting in a Fonitronic Cascade, which is a triple attenuverter + CV or audio mixer module. And for the last blank in the upper left, add a buffered mult as the destinations are approaching that "voltage sag possibility" zone. Or, use the existing Links for that function, yank the upper-left blank, slide everything up to the Kinks (also goes away) left, and drop in a SSF Tool Box to add a bunch of utility functions that'll be super-useful.