Hi Lindsay,
I am not sure if I can be of much help to you, as I too would like to get some ideas on themes for future reunions. However, I can tell you the past three themes we used for our 2000, 2002 and 2004 reunions. They were, respectively, the following:

1. Strengthening Family Ties Through Kinship, Friendship, and Fellowship
2. A Family Standing in Unity and On One Accord - Psalms 133:1
3. Sim-un-Ye (South African)/ "We Are One" (English) (with the family dressing in African attire at the banquet)

Melvin