One word of advice after watching groups self destruct. Do not try to playn every event that involve everyone all the time. Large groups self destruct when they put too much energy into getting everyone together, and of course Uncle Morty and Sister Whats her Name do not show on time, etc. etc.
The dinner tables hold only so many. Deal with it and realize that everyone else is at another table. Somebody once mentioned that the guest of honor (gram in this case) sat at a different table each night.