I know saying this will probably just get me a "git gud" type of response from anyone who reads it, but I just personally think if your game is inspired by a game that's known for being cheaply designed and unfair, you shouldn't stay too true to the inspiration. There were several parts of this game where I had huge trouble but with enough patience and thinking of strategies I finally beat them despite considering just giving up.
But then I got to the room in what I can only HOPE is the final level (the one where robots start appearing) where there's tons of those head-spider monsters and Medusa Head wannabes and shield guys and... yeah, I gave up there. It just feels bad to start out thinking "this isn't too difficult, why is every enemy so weak?" and by the end of it I've had so many failed backflips ignore the direction I'm pressing, attacks that still get me hurt, and so on that I can't find the will to push through it anymore.
The game was pretty fun when I wasn't being slaughtered by bats appearing out of nowhere every few seconds though, and in particular the boss that charges at you then turns into a head and spine was very fun to try to figure out and then succeed against. And backflipping was fine and often really cool, when it actually registered which arrow key I was holding. Like a lot of platforming type games, this one is very good until it goes very bad.