Not sure for the reason for the quantizer, though, unless you want to sequence VCF cutoffs. The Twin Waves (which aren't intended as LFOs here, but VCOs, giving four rather complex VCOs in just 16 hp) are internally quantized...sort of an unusual feature, but it definitely saves space + cost. The logical thing to replace it with, of course, would be the PICO MScale, as this would allow bidirectional CV conversion between this build and the Sirin, which fixes the Octone's inability to output negative CVs (which Moog stuff likes for some unholy reason). The Octone also internally quantizes, again sort of negating the need for a separate quantizer. Also, if you're removing the Batumi (bad idea, IMHO), the Poti would have to go as well, as it's the expander for the Batumi.

Actually, I'd suggest keeping the 2 x Mixup version, or maybe consider substituting a pair of Happy Nerding PanMix Jr.s for the Mixups, which would then give you panning over each mixer input. Summing down those into the Ciao! would then make a lot of sense. Also, it would be possible to retain the Chronoblob2 (for stereo delays) if you lost the 1U blank and the PwrChecker on the top row, which would let you swap the earlier iteration of the Chronoblob out. Last thing to do is just a position swap, then: move the RowPower 40 from the right end to the left, to get the power supply away from the audio mixing/processing in case a noise issue tries to sneak in. You'd lose your channel mutes, but that's not too disastrous...just have to twist a knob instead of flip a switch, same result in the end.