Have you tried PhotoFiltre 7 (it's an older version, prev.) had no layers but other features & as optionally portable software than casually downloaded? It's for 2D-art but can do shadows, texts, backgrounds, etc.
Do you plan that drummer to be like smooth (compared to pokemon movies) or pixelled (similar to pokemon-sprites in first gen. games), instead in chibi-style ...or which type of art in inspiration for the design?