Protip #1: Heavy Drums + Soft Delicate Piano = Huge Dynamic Dissonance. Its not bad to have Piano in the end or beginning for a Rap beat, but at least give it it's own space to live in.
Protip #2: Reverb. Reverb is pretty necessary in most rap beats to allow Instruments to give off "air" for the rap, without taking away from the rap. Without it, everything sounds stale.
Protip #3: BASS. You don't have any bass. Its a problem, yes its noticeable. It is very notice able. Even doing two 8th notes on a single note with in the same beat and repeated for each measure (ala The Beastie Boy's "Whatch'a want?" would be much better than no bass at all.
Other than that, this also could use more variations with the piano loop, as well as the synth mid song. Honestly, with that beat you got there, it sounds like the Melodies should be written in a minor key. Speaking of the Drums, it needs a lot of looking at. A lot of it is strangely timed and in-consistent with the exception of the snare. Normally, I like that, being a Progressive Sub-Genre Junky. But this is the Rap Genre, so it really feels out of place. The synth mid song is both not aggressive enough, and not in-obtrusive enough. I can't tell if its supposed to play over the rap or by itself, and its not suited to either task.
In the end, i'm going out on a limb and guessing this was like a "first song ever" experience.
So in the field of firsts, its okaaaayish. I'd like to see you continue, grow and improve. ;)
Cheers~
-Danielle