I'm having a 2:30 SBP wedding. We will have dinner at 5:30 and then a DP at 8:30. To be honest, I am kind of worried about all the down time. The ceremony ends at like 3:30, so what are people going to do for 2 hours until dinner? I guess it kind of depends on where everything is located. For us, everything is right on the Boardwalk, but if you are doing stuff away from the Boardwalk, then you can factor traveling time into things.
The only reason I am thinking our 2:30 is a bad idea is because it will be in June, and that is probably the absolutely worst part of the day to be outside. But if you are having a December wedding, I would definitely pick the 2:30 slot to eliminate the "standing around" time.