Very cool game! Not sure if I would call it a Metroidvania yet. That skating/grinding on rails mechanic is great though! I honestly think you might just want to make a platformer/racer game that focuses on that mechanic. It was so fun to hop on the rails and just go and then jump from rail to rail. Really loved the art and backgrounds too, very spacey and futuristic! The controls felt very very floaty, but like I said above once you get on the rails it is perfect.