Lots of great cheeses on pizzas besides the standard shredded and fresh mozz...
I've seen folks on this site using mexican cheeses. I usually stick to a base of mozz with other 'fancier' cheeses to bump up the pies. Some favorites: Ricotta, Goat Cheese, Provolone, Fontina, Taleggio (stinky foot), TARTUFO (with truffle), parmz, pecorino...
For many people pizza is bread with cheese on it so you really can't go wrong if you trust your tastebuds and find good local or quality imported cheeses..