You should add a 2 players mode to this game. It has so much potential which could manifest only that way.
http://www.nitrome.com/games/badicecream/#.Ys8hcXZBy01 Check this old game out. It will give you some very nice ideas to enrich the game I think.
Also, make use of the fire mechanics. "ignite this wall and stay safe 'till it burns out so that you can continue moving"
"drop some oil, draw a circle. Make water drop come inside it, then burn it so the droplet cannot move anymore"
Evaporation, light tricks, 2 player interactions, burning mechanics, and many others. Good luck with the game.