I've got a bunch of really ancient controllers on which I would not recommend you wasting any time. However, I hope to upgrade pretty soon probably to a Native Instruments Maschine MK3, a Studiologic SL88 Grand Hammer Action Keyboard Controller, an Arturia KeyLab 61 MkII 61-key Keyboard Controller, and a ROLI Seaboard Rise 2. Of these (and since you're already doing Komplete Kontrol), I think the Arturia series would be a great suggestion to consider for controller support.
In the spirit of FWIW.
Thanks for undertaking this!