I obviously can't post actual illustrations from the early reader I'm working on, but I can post color sketches. I do this kind of thing a lot since I have several styles on my portfolio-that way I can be sure I'm doing the type of art the art director is expecting.
I do plan on narrowing down my styles to just two, or maybe one at some point. But it's hard because I get bored so quickly and change around. On the other hand, I wouldn't mind getting super good at one instead of being a jack of all trades and master of none.