Ok, I've taken a lot of the suggestions on board, and I might pick up another VCO and VCF. My setup would look as follows:

-- photo shows old rack - I cannot get it to update, so just follow the link --

ModularGrid Rack

I do have a MI Veils module that is free at the moment, so that could be a winner.

Alternatively, I have a Waldorf dual VCA that is 20hp, and would fit the spot perfectly. I also have a Waldorf 20hp compressor module that would fit directly below. Thoughts?

I probably won't go that way, but maybe.

I'll start looking into some utility modules when I get a chance