We usually need at least a 1.5-2 hours session in a day, when we can take pictures from the couple together, away from others. It is advisable to bring your best friends as well in case we need a helping hand and to make you to feel more relaxed. It is better to let even more time for this session, so you have less things to worry about. All the remaining time is spent on the report-like photography of the events.This can include anything, we can follow our "general" routine and/or help you to realize your and your guest's special photo requests.
My rule is that if you have a special request or the given situation contains an inspirational moment, do not hesitate to have it shot. If you postpone it for later, you will probably postpone it forever... 99% of time these will be forgotten, because the day is so highly intense and there are so many other things to concentrate.