Thank you very much!!
I more or less understand your concerns and points and I can see clearly the overall is focused in space, lucky for me, this is not a major problem, but I clearly understood the point. I need to say something on this matter, I literally don't have small hands, and it won't be fun play around with smalls nobs and cumbersome 2HP/4HP modules here and there. I had to decide for the small mixers as a way to get some extra space, but I am still thinking on it. But certainly you are right, I need to look for another OSC, I need two VCO for sure, but they can be smaller than the PitsM. I was already thinking about it.
I know the Z8000 is huge and it can't work alone, but I will paired with the Korg SQ-64. And I will definitely look the Hermod module, this is exactly the reason I opened this thread.
And, yes, I need to think more about the clocking system, but overall the SQ-64 will take care of everything externally, I didn't mean to build a stand-alone rack, I will use my external gear with it. The SQ-64 can handle almost everything regarding sequencing, quantizing, clocking, even step gating/clocking the Z8000 Clock inputs. But, you are certainly right, I need to think more on this.
About Clock system modules, what could be my best option, taking in consideration I can generate divider/multiplier clocks from the Expert Sleepers FH-2 module when needed too. I was thinking in something like the 4ms QDC, but it takes 22HP with its expander.
Thanks again, I appreciate it.
Edit: I expanded the rack to 416HP, to show the two Mantis is a fact.