It's a quite a wonderful piece of music, and your rendition is very sensitively done.
Gary's comment about the strings I strongly concur with. It seems like you may have the full string sections waaaaay in the back, with the soloists unnaturally waaaay in the front. I'm afraid that for me, and it appears Gary also, it's spoiling the effect here to some degree. The rest of the orchestra isn't on a small scale - so there's a discrepancy in the sound.
How about checking those levels and making some slider adjustments in either Kontact or Finale? - Unless the small sound is something you're really happy with?
I agree with everyone here....tons of work and it is a very good effort. But you need to use the section strings and not the solo strings to give it the full symphonic orchestral sound. Rossini certainly did not write this for a string quintet. Just substitute them in directly and you will be home free.
I am not familiar with this piece (that is not surprising because I am lacking in my classical music listening education) but I really liked the piece and the rendering that you did. It sounds wonderful.