If you don't normally play classical, it might be difficult to jump right into the Ibert Concertino or the Glazunov Concerto. Try something that is a bit more straightforward, in my opinion, like the Dubois Concerto. Lot's of fun technique, a solid piece, but not quite as musically intricate or challenging as some of the other mentioned works that might put a strain on you if you're not used to performing classically.