How long do family formals take? Well that depends on bunch of variables. Here are some tips that can help this go smoothly and quickly:
1) Ask your family members to be nearby at the appropriate time (whether it be after the first look or after the ceremony). Have a specific area where they are to be at a specified time. Tracking down that one person for a group picture is a time killer.
2) Have a family member who knows everyone be point person. They can quickly find to the folks needed for the next group photo. Also, they can track down next group while the previous group is getting photographed.
3) Give the photographer and the point person a list of the family groups to be photographed to keep everyone on track.
4) Start with older folks (grandparents) on the list first. That way if they can't stand as long or if it is colder out they can be done.
5) Prepare family members in advance with advice such as taking sunglasses off, making sure ties are straight, putting down drinks, etc. Ask them to pay attention to the instructions given by the photographer and everything can go quicker and easier.