I agree with Matt on all counts: Nick was super in both bouts I saw him in. He is always high-energy, but spot-on with numbers and mindful of the sensitivities of the judges and competitors. Lynne Procope also hosted one of the bouts I competed in and I thought she was great, too; it was a very hot room with exciting performances, and she was level-headed and endearingly snarky (just a bit!) with the audience.
Naz (the Finals host) is an enthusiastic and efficient host, and someone I enjoy watching, but I think she was a little handicapped by the cavernous venue and inability to interact with the audience. I saw her host semi-finals years ago (St. Louis?) in a well-filled and well-lit room and I remember thinking at the time that she was the best host I'd seen.