You can try multi-step mashing to activate different enzymes in your mash that you wouldn't otherwise get in a single-step mash. You can do the following protein rests to break down a little more protein to activate different flavors in your beer:
- glucanase rest
- phytase rest
- betaglucanase rest
- protease rest
For the most part, your grains are going to be highly modified enough that you don't need to do these other rests, but if you're trying to go for a more traditional style and do multi-step mashes you can. However, you do run the risk of breaking down helpful proteins and ruining the head on your beer.