I really liked this song, its groovy :p, I hear you wanna improve alot, well, what you can do with the piano is kind of lower the treble end (not that much) with an equalizer of the piano and add some reverb or a delay. Idk if you know what I'm saying but basiacally it adds emotion to the piano :P
Idk if you started using mixer tracks but you can put drums into separate mixer tracks and do some stuff with it, like giving the kick more bass in the equalizer to make kick more prominent, and raising the treble for the hats to make it...click or something...
So good luck :P, it takes awhile to get around the workstation of FL studio but once you get the hang of it, it becomes a simple activity to do on your computer.