I clicked the picture and saw you already started making it bigger, and that's good. 84hp at least will go a long way towards making this a very good system to start with. What you need mainly is modulation. A Pip Slope does some good stuff, but also having some LFOs (Batumi, Ochd+expander, etc) and maybe a sample and hold (Toppobrillo Sport Modulator, Divkid RND Step), small CV sequencer, and/or quantizer will give you a ton of variety even from just the Ensemble oscillator and a filter. Effects are probably better left outside the rack for now, but that's something you can figure out as you go.