we had ours at 3 pm...That way we'd have plenty of time for pictures afterwards and then it was dinner time by the time the reception started so it worked out perfect!!
We had an evening candle-lit mass with an outdoor tented dinner/reception afterwards. We got married on a Friday night. We also had a formal brunch at the Bed&Breakfast we stayed at the next morning for "immediate family" (80+ --we only had 100 at the wedding, so it was almost everyone) and then a barbecue/bonfire at my parents farm for the rest of the afternoon/night. Since everyone was coming in from out of town/state it was nice to make a whole weekend of it rather than just the ceremony and few hour reception.
We did 4:30 with the half hour good luck idea as well. Also, I hate being a guest who has to kill time between ceremony and reception. Do you go home? To the mall? McDonald's? I hate that. So, I had a reception pretty much immediately following (6:00ish).