That's a serious system you're thinking of. As it stands, you could do some real things with that system.
I would worry that if you're new to eurorack, then you jumping right to that very sophisticated a system, you wouldn't deeply investigate each module's potential. I would start with a core set of modules, and step up from there. When I got Arbhar, I had to set it aside in it's own case so I could learn it by itself, without the distraction of the rest of my system.
The VCA suggestions so far are good ones. Tallin is a great sound VCA, but you'll want more VCAs, and something like the Quad VCA or the MI Veils will give you a lot more possibilities.
I'm not sure about the Vector for a system this size. Vector looks like a great sequencer, but it's only got 2 tracks, right? With as many voices as this system has, I would want a minimum of 4 sequencer tracks. Either Vector needs a smaller backup sequencer, or I would look into Eloquencer, USTA, Stillson Hammer or Metron with a CV expander. Don't get me wrong, Vector looks great.
You're on the right path, and you've often obviously really thought this out. Keep working!