It's not going to happen. Eurorack is expensive to begin with.
You expressed interest in jamming with your group. How do you intend to stay in sync with them and in key with them? Speaking of key... how are you going to generate pitches? You would need to add something like a KeyStep controller to this.
+1 on all of Jim's comments. You'd be better off spending $300 on a Behringer Neutron and a Kestep or KeyStep Pro.