You really love sidechain :P
The piano could really use modulation on those notes. Mainstream music used to think the happy-hulk-plonk was cool but in reality, it dies on the ears once you've heard it a few times in other songs and just sort of sounds generic. Velocity and modulation are your friends when it comes to "classical" keyed synths like the piano.
Vocals aren't really sticking out. Could use some compression, chorus, EQ -- they're really drowning in the (admittedly pleasant) instrumental. It's like trying to listen to a conversation in a club when all of the sudden the crowd's absolute JAM comes on. The end result is struggling to hear what the hell the other person is saying. Would be fantastic if not for that. Make the vocals pop, so the listener doesn't jack the volume until their eardrums do trying to hear them.
Thanks for the review request, and sorry it took me a year to get around to them. Depression is killer, I tell ya. Anyway, hope this gives you some insight for future mixes.