Get a second hand Oberheim MC3000. 48 programmable velocity curves. For example, Rhodes need to be struck hard to make 'em bark. The grand piano needs a different one. My point being that this controller is customizable per library, and has after touch. It only lacks polyphonic aftertouch, which would be helpful for your scenario. Each key would trigger a different aftertouch curve, not a global response, but polyphonic response.
But my MP9000 doesn't have aftertouch like several master keyboard
Yes, that sucks that the Kawai's don't have aftertouch, I also have an Kawai (MP9500 Stage Piano). Its funny, that my Alesis QS8 has aftertouch, but the more expensive MP9500 does not. Regardless, it is a fantastic controller for piano through.