Thanks guys- it took me a certain amount of flailing around to get the modular sounding decent. Gain staging inside the instrument is more important than you first realise (feel free to point and laugh, as it's obvious in hindsight). Each module has its quirks and requires familiarity and obviously the permutations get complex quite quickly.
I had a lot of misgivings that pursuing it was a mistake- but eventually it started to to sound the way I wanted. I've been enjoying weird non-linear workflows, which were what I was hoping for at the start- it's more like flying a steampunk zepplin than playing a piano. It's totally possible to build "normal" instruments with it, but where's the fun in that?
(At least, for me, who isn't a proper musician, and mostly listens to things that aren't proper music..)