Another option is to split your program into two distinct parts. You could do this with either DRUM or keygroup program types. For example in a keygroup program:
1) Set up a piano instrument samples to cover the required key range; for example A0 to C6.
2) Set up additional keygroups to hold the drum samples, but only use the notes that naturally appear in bank A, i.e. C-2 to Eb-1. For example, create a keygroup covering only note C-2, set to 'keytrack:OFF' and assign your kick sample to it. You can now trigger that kick from pad A1 (which is note C-2).
Now you can use the controller to play the piano with your left hand and your pads to play the drums with your right hand. As this uses a keygroup program you'll have more control over the quality of the instrument sounds (i.e. note range can be more than 16 notes, option of multiple short range keygroups etc) although less options for processing the drum sounds. If you need more control over the drums, create it in a DRUM program instead. But you'll need to reassign the MIDI notes on the pads to make them chromatic - do this in the MPC Software (Edit > Program > Note Mapping).
I'll write up a proper tutorial and post it up to MPC-Tutor asap.