I agree with Progspiration on almost everything he said - basically you are trying to do too much in too small a space
either start with a bigger case or massively scale back what you are trying to do
you'll need more modulation - and someway of mixing the 'ordered' modulation with the chaos - a matrix mixer in my opinion is best for this - and one that is usable - ie ergonomic and therefore quite large - I like the doepfer - plus more attenutaors - not just vcas (and you haven't really got the envelopes to open and close the vcas anyway
I'm not really convinced that the combination of the poly chromatic and bloom will work very well together - I think you really need at least one (preferably 2) channel(s) of proper sequencing (or a midi sequencer) to make the most of poly chromatic - one channel to determine the root and another to determine the chord type
personally I would go for the bigger case and spend a decent amount of time (a week at the very minimum) thinking deeply about the hints in my signature... you will end up with a much more versatile modular for less cash (in the long run)
"some of the best base-level info to remember can be found in Jim's sigfile" @Lugia
Utility modules are the dull polish that makes the shiny modules actually shine!!!
sound sources < sound modifiers < modulation sources < utilities