Can somebody give me feedback on this mixed trio?

https://musescore.com/user/58321165/scores/19807804

The opening theme has a renaissance feel.  I found it quite interesting and enjoyable with a dance-like quality.  Have you thought about using a Recorder or Shawn instead of a flute; this would give it a more authentic texture.  As for the rest of the work - I felt your later attempt at various variations to be less effective then the opening which from my perspective is more  direct with less noise. 

Mark

Hello @Neo36563 and welcome to the forum!

Is there any particular reason you chose these three instruments to write your trio?  It seems an odd combination.  For me it brings connotations of some kind of toy-soldier march.  But the texture is mostly monophonic because for most of the piece the flute and trumpet are doubling each other.  There are notes here and there that are different between the flute and trumpet which create harmony.  But overall, the texture is still pretty stark and empty throughout with the little differences between the parts adding little to the overall impression.  My suggestion would be to try writing for a combination of instruments that includes at least one polyphonic instrument such as piano, guitar, organ, accordion, celesta, or any of the pitched percussion such as vibraphone or marimba.  Thanks for sharing and I hope to hear more of your music!

The sound is very hollow throughout the majority of the piece. Your rhythm is interesting, but in some spots, it feels very random, especially when all 3 instruments are playing different rhythms at the same time—it just sounds jumbled.

This may not be the sound you're going for, but try your flute harmonizing in 3rds or 6ths above the trumpet, I do that a lot b/c it keeps a solid interval in the harmony, while also accompanying what's already written for the main instrument.