I liked most of your work. The return and Delectro being maybe the best ones.
Cyberpunk had some Vangelis vibes in it and Delectro was sort of a mix between Kraftwerk and R?yksopp.
Some songs had minor flaws just as ZhaoYun mentioned. Mystic Mountain - Ride on the Giant's back had strange ending. Delectro felt little bit unbalanced and leaning more on the left side on my headset.
I don't think "The return" needs mastering as it's more soundtrack music and needs some dynamics to sound massive as it does now.
I'm not professional with music, but I do make music as a hobby for my game projects.