Pretty fun arrangement! A lot of the patches don't really work convincingly atm though - add more variety in MIDI programming, or beef them up with additional patches etc! If you need to, you can adjust the arrangement to cover them up as well - doubling a so-so viola patch with a decent violin patch an octave up works pretty good, for example.
The brass really needs some variety in velocity, repeated notes like those in brass screams of digital orchestra!
About the arrangement: would've been nice to seen the cello melody in the start doubled an octave up (at least after a while) with arco, to add a little middle register. The pizzicato doubling is a nice effect though, definitely keep it!
Piano sounds could perhaps use slightly more reverb, it stands out a little and sounds much "closer" than the rest of the instruments.
Still, was a fun listen, keep at it!