Man, after playing this, I kinda regret not making more platformers. Yes, it has risks but the only reward is a higher score. Like, you can still finish the game just fine without getting any of the riskier coins. The movement is kinda rough around the edges but the main mechanics, grappling and dashing are pretty well implemented. A lot of people will probably suggest you work more on the player physics (like adding coyote time) but personally I recommend going to the basics, like having a game over screen or fixing the transparency on some of the sprites, maybe even updating the font to something more pixel perfect to match the rest of the game.