Nice!! For my ears, a lil percussion (some scattered hats or something) to fill out some of the more empty parts of the song would add a nice flavor. Also perhaps some transition sounds between parts.
You're mix is good! Could use a little more compression/limiting. I feel like some of your synths and drums get a little covered up in the mix during the busier parts. Great work though man! Can't wait to hear some vox on it!