At the very least get another Intellijel midi module to allow more control via the OT.

I find you can never have enough mixers and attenuators to allow for more control over the full strength signals. Acid Rain Junction is very neat and compact. It can also operate as a mult which I also think you can’t have enough of.

If you’re making drone and ambient consider modules that might enable feedback patching. Bastl Dynamo is pretty neat.

The Versio range is really great for ambient stuff and can be flashed depending of what sound you’re after.

Low pass gates always sound great on hard oscillators. I particularly am digging the Steady State Gate as it can work as a filter, has distortion and can plop out envelopes.

Have fun!