Hmmm... When I'm feeling creatively challenged I usually trying playing with a different figure.  Sometimes animals are a little easier to do than people because the emotions aren't as complex and often you can just render as is.  In addition some of the tricks that you can learn from animal studies, just as perspective, lighting, and composition can be later applied to human figures.  Plus, the advantage is that you are still productive while you are trying to sort out what subject matter that you will like to take on.