As far as filters go, I assume you want some that don't take up a lot of space or use a lot of current. Some that I have and like that meet those requirements would be:
1) Bastl Cinnamon
2) Karltron Steiner Parker
3) Mutable Ripples V2
4) TipTop Forbidden Planet
5) Nano Font
6) Doepfer Wasp
-- adaris
Thanks, I'll take a look. I was going to go with a simple Pittsburgh Modular mixer. I'll have a look through you suggestions.