It would be nice if you could show the other players in your group on the map, or a place where you could tell who was in your group. I hate when i get into a group that is full and i dont know who the 3rd person is.
This is just what I was thinking and it does get annoying from time to time, it would also be great for your buddy list to, in order to group with them but see how far they are from you.
Group Mapping
