Family formals are typically done at the ceremony location, or somewhere scenic nearby. Let those family members know where to be for photos so they don't wander off.
I suggest leaving this part to just immediate family (parents, grandparents, siblings, in-laws, etc.) I've seen it before where there have been some hard feelings were some extended family were included but not others. If you want some extended family photos, this is your day and we can totally do that. Just know it will add some time. I typically say estimate about 2 minutes per photo.
These photos are more formal, but we can make some time during the reception to grab some snap-shot style photos with anyone else that you would want photos with during the reception.
Any photos with small children should be first. We may not have that long for their cooperation. After that should include anyone with any standing or walking restrictions, that way they can relax and not have to worry about being up and down.
When making your family list, please use first names so that my assistant can easily call people up when it is their turn for photos. Include any variation of photo that you want. Typically all the group photos include the wedding couple, and then solos with individual parents and grandparents.