you could make the player a greedy Leprechaun and his pot of gold for a theme. Fun and interesting game idea. I think there should be a different visual for when you are holding the coins than changing color, like if it showed the player holding them above their head getting weighed down by them as they collect more and more coins. With that I think it would be clearer what's limiting the players jumps. Then just tell the player to get all X number of coins in the pot. I checked out your other projects and you have a lot of cool and interesting ideas with a lot of potential.