I find After Touch to be the most valuable expressive modulation routing, freeing one's feet to have any other(s) midi cc assigned to an expression pedal. The newer Moog EP-2 expression pedal has a special potentiometer that allows one to set and/or limit the range of assigned parameters.
Assigning Breath Control midi cc to After Touch or filter freq or resonance, saturation, really allows some intense sound sculpting!
The Virus KB and KC and DSI MEK and waldorf Blofeld Keyboard all share the exact same superb Fatar Keybed that happens to have most playable After Touch as far as expressiveness.
Rant over (did I mention I really love after touch?)
