What would you fill this 20hp with?

My rack:
ModularGrid Rack
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What would you fill the remaining 20hp with? I was going to put a SSF Ultra Random and a monome walk + ansible. But now I'm thinking maybe ad something else... Love to hear ideas!

Making mostly experimental / ambient stuff... http://sleeplesswaves.bandcamp.com/

Cheers!

Well, it seems to lack some complex random-type functions, so 18 of those 20 hp maybe oughta be a Marbles, especially if you're out on the experimental end of the spectrum. Ultra Random is...OK, but Mutable's new take on random is just plain nuts!