I just saw a free improv show tonight at Muchmore’s, they have a decent QSC system. Booking happens through their website.
There’s also H0l0, which does a lot of experimental and modular stuff, though I don’t know how to book there and it might be overly saturated. And Trans-Pecos, The Glove, and Secret Project Robot, which are bigger spaces in Bushwick/Bed-Stuy. I know there are a couple other venues in Ridgewood that book stuff, but I can’t remember their names. I’ll look into it.
I don’t perform modular but I do a lot with Max/Monome and live instruments. I’ve been working on a duo with a friend if you need more performers.