How about instead of a box they expand the your idea into a 12 channel small board mixer just like the roland mx1.

But with tbe following features
- Midi in input and midi out output
-4 aira input usb channels
- one aira output and input channel with ability to send and receive usb audio, midi clock signals to other daws like Ableton. Just like an aira instrument
- one universal sync play button. But all also above every channel add a play, stop , pause button for ableton use .All the serato scratch live bridge features but this time named serato bridge.

- two sound cards for the board mixer, so that one can be assinged to a daw
-on board serato sample features with sample banks assignable to individual channels
- two mic inputs
- send and return
- then all features of the roland mx1