That's what, 18 HP to fill?

I'm thinking:
Beehive (micro Plaits clone), 8 HP - Wavetable oscillator
Xaoc Tallin, 6 HP - 2 more VCA's with overdrive/distortion
Then pick some 4HP utility, maybe a Disting mk4, FX Aid, Divkid Trace or ochd...

You could save a little space by replacing the Line In, Line Out, and Headphones modules with a single Stereo I/O 1U. That will do the same thing but in 20 HP instead of 30. If you do that, and get rid of the 6hp blank, you can free up 16 HP of 1U space. You could then fit a Nonlinearcircuits Sloth Chaos & a Shakmat Tessitura Tailor.