The animation is beautiful, and the backgrounds are gorgeous. It looks almost professionally done.
The way colours are used makes it obvious that the animator knows what they're doing. There are some minor pacing issues in the fight scenes but that's basically nit-picking.
There are places where more sound effects would've immersed the viewer into the world you've set up if they were there; think more about environmental-acted sound-effects like stepping on sand and sliding across it or a whoosh as a person is tossed through the air.
Obviously there's also the voice acting and script stuff, but that could be easily fixed with an editor or such. But pilot-wise, it doesn't do much to introduce the viewers to the world it's in or the story.
Perhaps that would be something well to look into.
I look forward to seeing more from you.