I tried to keep the processing very light. With all the bleed any drastic EQing shows up so I kept it simple. Very light compression and reverb. They play with great dynamics on their own.
The piano sounds very close to the listener on the right hand side. It could use a rethink on the imaging here. The piano is also quite midrange strong, and it seems the bass and the piano are both sometimes competing for the same space. It's a slightly claustrophobic feeling that comes from this.
Thanks for the feedback, here are some changes. I reduced the pan on the piano and tweaked the EQ across the board, and added a stereo widener to open things up.