I love that jazz!
First of all, this song deserves more that the 2.87 it had before I voted (which made it a 3.18). Also, change the genre to Jazz ASAP!!!!
Now for imporvements, I recomend adding some nice improv solos in the middle inbetween te main melodies. And then I would take all of that non-melody stuff and use it as backgrounds during the solos which should be at least two forms long each. That would help this song a lot. And at the ending, take what you have and ADD the trumpet playing the lick up an octave after the rest play it first. If you need a better idea of what I mean listen to some profesional combo jazz or the like and see what they do.
Also, 0:36 to about 0:54 would be good for backgrounds (as mentioned earlier).