You mentioned your difficulty mixing vocals, but I feel like you did so in a way that compliments the track. They could be a few dB louder, but that may just be my own preference -- and maybe a little bit more of the 8k range on the EQ. It sounds phenomenal otherwise.
Your synthwork is perfect, except for the obvious synth bass. Maybe work a little bit more on modulation so the attack doesn't seem so droll. Other than that, stunning work. I know it must have taken some time. Great tools help though, of course.
Stellar work as always, Step. Just don't be afraid to crank up those vocals a bit more, so the instrumental doesn't overshadow them. Background vocals were implemented perfectly, I must say.
Keep up the great work, and thanks for the request!