Made a demo:
14input/7output Character Mixer
https://steadystatefate.com/products/vortices
Made a demo:
Nice demo.
I never really drive the signals through my Vortices, I'll have to give it more experimentation.
Enjoy your spare HP, don't rush to fill every last space, this is not like filling sticker books. Resist the urge to 'complete' your rack, its never complete so just relax.