i can't say that i'm an exemplary mastering-master but there's this helpful line that improves your mix a lot - http://hyperphysics.phy-astr.gsu.edu/hbase/Audio/imgaud/whitedb.gif
mastering/mixing to pink noise.
Why?
Because higher frequencies are more easily heard and therefore can be made quieter, while bass can go a git louder, as a result they will kind of sound "right" and "equal" to the ear.

I also noticed from 1:05 until 1:15 there's one of the synths clicking all the time on every note it plays, it probably has to do with attack of the synth, making it a bit slower can fix it right away.
Piano sound dry to me, just a tiny pit of reverb would make it more realistic as if it's in the room and stuff, just normally we don't hear anything without it's environment, which reverb creates.

Also don't worry about "score" and "good reviews" what only matters is making mistakes and fixing them, which will make you an expert on this stuff, have you heard that phrase: An expert is someone who made all possible mistakes in a specific field. which in our case is production.
So grab a few mastering videos from youtube, mix to pink noise and keep synths from clicking by not making too short envelopes. Good Luck! Keep on getting cooler each time! :3

overall I'd say it's nice
the really high pitch sounds at 0:40 and 3:30 are a bit annoying
but I liked that you brought in some more variation than the original imo