The floaty controls are intentional. I put the coins in the menu, but sadly there is 1 bug in the entire game and that bug happens to be that opening the menu in the shop breaks the game. Although it is quite simple to fix. I also decided for floaty controls due to how I wanted gravity to work in this platformer where some jumps are quite high. Overall though, thank you for your detailed description of the game :) (although I do think putting the amount of coins a player has in the shop, to be pretty nice)