Here's something I actually do though, I take frozen pizzas and make them more special and nutritious.
For starters, you can lightly cover them with olive oil before baking using a cooking brush in order to add juiciness to the pizza sauce and the crust. This is such a good trick that even pizzeria (real ones) chefs use this sometimes.
Next is cherry tomatoes. These will further improve the flavor of the pizza sauce, by adding some real fresh tomato to the mix. The pizza also becomes less dry and salty overall.
Mushrooms will bake along in the oven and turn out delicious on your pizza. If you like them on pizza, that is, I heard some people are not fans of the funghi.
If you still want more flavor, you can try sprinkling fresh pesto or olives on there for a real Italian experience from a frozen piece of garbage. I also like to dip the crust in hot sauce.