The FH2 is probably an overkill unless you plan on hooking this system up directly to a computer. You could save a lot by using a simpler interface. The FH2 has some interesting capabilities. But programming it is a pain in the... If you simply want sync, you can get the MIDI expander for Pam's New Workout.
Pam's New Workout and the Mimetic are a good pairing. I'd add a micro Ornament & Crime unit to this (8HP). It has a quad quantizer mode that makes getting really nice, in tune notes out of the Mimetic. O&C has other functions as well, so it'll be very handy.
Your rack has no LFOs, no dedicated envelope generators, no utility mixers, no basic utilities (like attenuverters, noise). You'll find the boring utilities are the glue that really holds your modular system together.
Also a small multi-effects unit can make a real difference. You may want to try an Expert Sleepers Disting EX if there's room. It's a Swiss Army Knife of functionality and will help you explore the possibilities of modular synths.