And just to clarify: I've given a lot of long-winded feelings and advice, but that Doepfer VCA is the only thing that I'd caution you as being an actual mistake. You won't be able to separately control your audio and filter envelopes, nor can you use the extra VCA channels for "general utility" purposes since they're locked into your articulaiton curve.
One option would be to replace that Doepfer A-135-3 with an A-135-2. This sacrifices the stereo capability of the -3, but gives you individual CV for each channel, individual VCA outputs, "Sum" output (ie the mix of all 4 VCAs), and "Select" outputs (ie the mix of all VCAs where you didn't directly patch the output).
Other option would be a more full-featured VCA like the Intellijel Quad VCA, ALA Cloaks (a clone of MI Veils), or Behringer Four Play (a clone of IJ's Quad VCA, if you're not opposed to Behringer). Or, the Doepfer A-135-2 alongside the A-135-3 as your output mixer. All of these have each of these features per individual VCA:
* Mono Input
* Mono Output
* CV In
* CV Attenuator
* CV Offset (not crucial but nice to have)
* Linear/Exponential CV response (not Doepfer) (not crucial but nice to have)
* +6dB boost (IJ/Behringer only) (not crucial but nice to have)
Plus, they normal their output to the next output, allowing them to work as a pseudo-mixer in addition to as a VCA.