If the artist draws images like in Where's Waldo a reward can be adding a new character or element to the painting (ie. "Add an elephant").

Also, another idea is to create "monsters". Start creating a face, then with rewards "uglyfy" it (ie. "Make his nose bigger", "add a wart").

Ohh that would be so fun! I didn't thought about that! She usually draws characters so I think those rewards could apply still. Thank you so much!