The Axoloti looks great! I mainly have the OP-1 to make a chiptune OST, but Axoloti Patcher seems like it would be more functional. What I really want is something that can emulate old gaming console chiptunes and be portable.
Or, maybe what you want is Anaologue Pocket?
https://www.analogue.co/pocket/
Dunno if its shipping yet though..
Maybe Axoloti is the answer. Its a very nice bit of hardware, I should use mine for things more often...