I really like your general idea of using metal instruments (brass, metallophones) to make your piece sound more like something from a steampunk world. Great choice!
You said you are new to DAWs. If Linux is your only option for an OS, you might want to check out LMMS or Reaper - I'll admit that my experiences with Ardour are not super recent, but back then, it would have stopped me from making music, if it was my only choice.
One of the things I noticed is that the glockenspiel is basically going unchanged, making it a little boring. Maybe it would be worth considering adding some volume automation to that track to push it a little into the background, once the other instruments are supposed to take center stage.
As was mentioned in another comment, your modulation from 0:45 to 0:55 feels a little awkward.
Overall, this is a nice piece with some interesting harmonies.