Are low crowds and mild weather your only two criteria? Just clarifying so you get the best advice possible. What temperature range are you looking at to hit the mild category? Are nighttime shows like fireworks, Fantasmic, World of Color important to you, or just rides? What about parades--daytime and nighttime? What about having early morning hours (open at 8am) and late evening hours (open until midnight)--or is 10am to 8pm enough?
There are so many great people here you will get great advice but this info might help narrow it down for you.