that was really awesome, loved that you could build a whole game completing the challenges, reminds me of arcade store where you need to push new coins to get them to push other coins out! I think you could make the character move using your mouse, making a weird movement physics, that way you could be achieving the "mouse only" challenge as well.
I also made a game about getting coins, you are the chest in a dungeon and you need to get big, if you could check it out