How are you creating envelopes? I'd definitely consider a Xaoc Zadar or an Intellijel Quadrax or something along that line.
Also a multi-effect processor like Happy Nerding FX Aid.
3x MIA has already been recommended, it's great.
Something with the capability to play one shot samples, like Bitbox Micro, Squarp Rample, Erica Sample Drum etc.
Maybe a bigger case for all these :D