Pam's can do random, logic and looped random quantized pitch - so I'd hold off on the instruo random and logic and the turing machine for now
the qpas and the mfx will probably be enough filtering - so again hold off on the instruo filter
I'd seriously contemplate the 2 instruo dual vcas with a quad cascading vca - alm tangle quartet or the intellijel quad - more functionality in the same space and for less than 1/2 the price
I'd probably replace the 2 adsrs with a peaks clone
the instruo lion I'd also hold off on and get a simpler matrix mixer - firstly so that you get a good idea of what a matrix mixer is and how it works and secondly because I'd lose the dongley bits (the i/o and the loop cable) - also less expensive - go for a doepfer for example
I'd look at your mixing solution in general - the instruo vco could definitely do with a dedicated sub-mixer and the end of chain mixing looks poor - no send/return
I'm not convinced of the benefits of the xpan either - a happy nerding pan mix jr would take up less space and be much less expensive
I'd probably leave the percussion module for case number 2
I'd also want some sort of delay and reverb in there - which you might just about be able to squeeze in with the space savings
there's no need to fill the whole case straight away - go slowly and buy a single voiced minimum viable synth and go from there
I'd suggest taking a look at my signature and spending some time thinking about it before spending any money
"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