On Radiance last month we never waited more than 5 minutes for a pizza. They were doing it right with about 5-6 people (total) working dough, toppings\cooking and serving stations.
I don't know about the new Carnival ships but on the older ships, the pizza kitchen looks terribly small. I am having a hard time believing they will, in the same cooking area, be able to offer more food selections. I dunno, maybe they will just bring in trays from the buffet area. Who knows.