My favorite is probably one of Brahms', probably the second, but I'm learning Rhapsody in Blue right now, Gershwin. I'm playing it with the Pitt student orchestra in April '05 -- a huge gig for me. I even am writing a little online journal about it:
www.alexryan.net/rhapsody.html
It's a great piece to be able to whip out when the need arises.
I looked at your journal a bit. A tip, since you were having trouble with "those sparkly figures that rain down from the high octave" (in no 9). Play the last triplet with your left hand! That's was I did, and it certainly helped. That way, you don't have to do that arm movement.
Listening to your recording now, it sounds really good! I can hear that you have worked on it a lot. Be careful, though, in 22 for instance. Piano must be played very lightly here (you played way too heavy for my taste) and quietly. You're just an accompanist here. Same goes for your left hand in 25. My teacher said it reminded him of some old banjo player, who's just striking the chord right on time and doesn't lay any emotion to it. For instance, if you do a crescendo in the right hand, try not to do the same thing in the right hand. Of course, this is a matter of taste, but I think the accompaniement was too loud in that part. You need to play it more softly.
Another thing is the agitato part (before the big piano glissando where the brass starts playing), where Gershwin marked that you should start playing slowly and and make an accelerando. You played it in the same tempo all the way, though. Try to make it sound a bit more mysterious (another thing Gershwin wrote in the notes).
But most of what you play sounds really good already. I'm absolutely sure that your gig in April 05 will be wonderful, and you'll have much fun performing this. Good luck! If you want to, check out my version of it with school orchestra, it's right here:
https://www.angelfire.com/music6/fnork/
Topic: Favourite Rhapsody