A couple of points here: first of all, yes, lose the uZeus immediately. Never add a power supply to a powered rack (unless it's something for a specific module, such as for some tube modules). And more VCAs is good. The Optomix is actually a pair of low-pass gates, which consist of a tandemmed low-pass VCF and a VCA, and this is fine for controlling audio levels, but having a couple of linear, DC-coupled VCAs for controlling CV and modulation levels is also strongly advisable.

Beyond that, I would suggest looking into a couple of dedicated envelope generators, ADSRs in particular, plus a couple of LFOs. While the Maths can do both of these things, it's much better when it's used for complex modulation curves, using its own internal subsections to create complicated CV/modulation patterns that go beyond what basic EGs and LFOs do.

As for Rings and Clouds, keep in mind that Mutable discontinued Clouds quite some time ago, but they still make the Rings module. However, both are available as third-party builds from several manufacturers...which is a bit of a plus, as those companies offer these in smaller form factors than their originals.