First off, Welcome to Newgrounds, I hope you enjoy your stay. :)
From a first impression, this piece is nice and rather pleasant to listen to, with good drums, melody, and progression. Although I dislike overly repetitive figures, you do a good job transitioning into new themes and motifs as time passes so not to bore the listener (you have that same "keep writing new passages until you find a good stopping point" mentality I have, it seems XD).
One thing you should work on is clean transitions- things like percussive rolls (cymbal, drum, etc.) to smooth over a sharp transition- in orchestral music, cymbals are your best friend.
I find the piece to have rather flat "highs" (such as around 2:00), it's barely different in volume compared to previous parts. There you must push further and transcend the bounds- be it a key change, or additional instruments (you could add a full chorus, a counter-melody on cello (consider counter-point and a running counter-melody that is prevalent), or so many other things... I did notice you added rather quietly some trumpet).
The style of the piece is very contemporary and only orchestral by the fact that it has strings. I honestly see this, no offense, best put in a sideshow of a vacation or a trip or perhaps a montage-style cut in a film. I still enjoy the piece greatly, as it does well with the chief quality of all cinematic music- to pass on emotion.
In that emotional regard, there is a rather odd side; although it is a relatively joyful piece, it has sentimental, if not sorrowful moments. This essential "two-tone" style of a happy passage and a sad passage is a really good way to go when working on original pieces.
Mixing is well done and the piece is clear.
May I ask, how long have you been composing? Have you taken classes in Composition and/or Scoring?
Good work on this piece, I hope to see more in the future. Consider posting your work in the Review Request Club thread or advertisement thread in the future though. :)