Not bad at all. You will need to swap out the 4ms power for the Arturia P/S unit, however, as it comes with the EuroBrute cab and it's 5hp, not 4. This will change the spacing on whatever row you opt to put it on (I advocate for the lower...makes dressing the power cable off to the side easier). Losing the buffered mult should give you the room, and it's pretty unnecessary in this small a build. I'm assuming this sends its audio back to the MiniBrute 2s? If so, make sure to check the specs for its external audio in, because if it wants line-level, it's going to really need it, as I'm pretty sure there's no way to trim down the voltage level on that synth itself. Easily dealt with by swapping out the FX send/return module.
The build's also a little filter-heavy. Potentially, losing the uHC would be sensible, because the Sara VCF is pretty complex in of itself and the Optodist will do much of the distortion the uHC would be up to. That way, you could swap in something more complex, random-wise, to go with the Noise Rainbow; Doepfer's A-149 series wouldn't be a bad choice, nor would an Ornament and Crime build...in fact, that has the potential of lots of extra functions in a small space.
Good move with the Attenu8, also...given that it can be split in 2, can do inversions, and probably a few other twisted tricks. Doesn't seem to conflict with the Quad VCA, but I would actually suggest moving the Attenu8 to the bottom row so it's handy for processing/controlling/mixing signals either going up from the MB2s or back down to it...or both!