I think it kinda depends on what you'll be using this for. This could probably be great for certain gaming applications. The music is good, but sonically, I think some things could be done differently.
I don't have much experience emulating orchestral sounds, but some of your strings sound a little unnatural. I would mess around with the attack/release times and note velocities some more. Sounds like you could also adjust some of the articulations, if possible. I've never used Symphonic Orchestra, but I would imagine there are a few ways to adjust the characteristic of different notes so they flow together more naturally.
Lastly, many of the instruments (especially the strings) could benefit from more reverb, or possibly a different kind.
Good work so far!