Hi Sean
Here is my feedback about your good mix (high nieveau).
Nevertheless, I have some hints. I've downloaded your mix for going deeper in it... ;-)
Stereopositions
Good are those of the strings and the woodwinds.
An improvement I see with the position of the brass instruments. They seem to be everwhere and nowhere. In the meantime the correlation is 0 and often within the minus range when the horns and trumpets are playing. So I suspect that you used a stereo enhancer (too much) for the brass instruments. In any case you should have a look which part/instruments lead to this negative correlations. Maybe you will get more definitions for the positions of the brass.
Frequencies
Good (OK) are those of the Woodwinds.
Improvements: The Strings sound too thin (shiny) compared to the other instruments and probably a bit too quiet. The opposite with the Brass instruments (Horns). They sound dark and a bit "blowed up" in the low frequencies compared to the strings and the woodwinds. So fitting the sounds of the different instrument groups to each other could be a task here.
Further: Your mix contains frequencies down to 20 Hz and lower on a "high level". Your music doesn't contain such low tones. This tells me that you probably didn't use Low Cut Filters for each instrument (except the lowest bass instruments of course). Low Cutting the horns will probably remove their "blowed up sound" a bit as well.
In general
Your mix is not mastered. The frequency range is not optimal used at the moment.
Finally - after doing the upper improvements a nice done mastering process will improve your mix even more...
I hope you see my hints the right way. All these proposals are improvments on a high level.
Also see that I'm doing recordings of classical orchestras and mastering tasks as a professional.
So once more: Your mix is OK so far. This also explains probably that nobody made any feedback until now.
All the best
Beat