I like this recipe--light and colorful.
Just made it for the first time, only changes being that I read reviewers here, and doubled (tripled?) parmesan. Also, I added some bacon chunks.
For the purple color, why not add 1/2 red onion? Sliced cherry tomatoes in lieu of the diced medium tomato would add a fun texture. Also, I think diced ham, or salami would have been great here, in lieu of the bacon that I added.
Nice open recipe, seems like there's a lot you can do to add your favorite ingredients in, too.