At 1:30 instead of just staccato flutes playing the ostinato you could double them with oboes, and then clarinets and bassoons doubled down the octave. If you're brave enough you can try some other intervals here (3rds and 6ths).
One thing I like to do is double winds with light harp plucks for added definition and color. Might be an option here.
The horn here (or is it a trombone) is kind of lonely. You could double it down the octave with tuba.
The timpani hits could be doubled with cellos and basses playing staccatos in octaves (I often use spiccato patches for this.)
You might start to notice a pattern in my suggestions. While the structure and composition are good, the main focus of orchestration should be on color, in which case unison/octave doublings are your friend.
At 1:50 you will want more of a build to the next part. You could do a brassy swell here in C minor.
At 1:53 the violins are too light. You'll want a marcato patch with a strong attack here.
Here you can also thicken the brass harmonies with some 3rds. Think of these as Bach-like organ chords.
At 2:05 you will likely want this quick melody to be doubled across all the strings and winds, and piccolo as high as it can go.
At 2:25 the doubling here is good, again piccolo should be doubling at the high extreme. If you have bass trombone it could double at the bottom. For definition you can add xylophone strikes. Another possibility is brassier trumpet "stabs" if you have the samples.
At 2:40 the violins should be doubled down the octave in the 2nd violins and violas, maybe even cellos. They can be additionally doubled by winds and/or horns.
The trombone at 2:44 sounds like a solo patch. Do you have ensemble patches? If not I would recommend octave doublings.
An instrument often overlooked in orchestration is the piano. Low piano octaves can really enhance your bass instruments for pretty much the entire piece. They double low strings, low brass, and sound great doubling timpani hits.
Another color you could add is the harp glissando. They work especially well to fill in gaps. For example, at 2:25 you could have A minor glissandos filling in the spaces between the rhythms.
Let me know if you would like more suggestions.