Hello,
First of all, I apologize if this is already a feature, I must have missed it. Under default settings the white key's aftertouch sensitivity is just fine but with the black keys, I thought I would just need a little practice but it really is too much, I'm starting to worry that I'll eventually break a black key given how hard I have to press down on one.
So, putting in a feature request for the next firmware update, please give us a global option to increase black key sensitivity separately from the white keys. From what I understand, there's no particular technical reason this shouldn't be possible.