Once of the problems I have found with having a few guildies playing in a larger alliance group is that I never know where they are.
I would suggest:
1. Group leader should always be a special color so we can see at a glance on the map where he or she is.
2. Guildies should have their markers a different color than the basic white over their heads so we can easily spot where they are on a map.
It is a pain having to drag my cursor over all the white group player markers in a large group to see where someone I want to run with is.
Once of the features in DAOC is that the names above guild members where always shaded differently.
cheers.