So many good combos. Here's a few off the top of my head that I like.
Bacon, pineapple, jalape�os
Bacon, green pepper, tomatos, feta
Garlic butter instead of pizza sauce, grilled chicken, tomatos, onion, banana peppers, feta, oregano
Straight pepperoni is always a good choice in my opinion. I feel like red pepper flakes, oregano, and feta can almost always be added for bonus flavor, but they don't always work.
I worked at this one local pizza shop after high school that my friends family owned. We made this one called a coney pizza that had coney chili instead of sauce, mustard, mozzerrella cheese, onions, ground beef, and hot dog slices. It sounds pretty gross, but it was actually pretty good.