I have been a Ranger Wolfman and Valar Templar.  Both are fun.  If you want to
play role-playing type guilds, Templar is pretty cool - especially if you have
a friend-templar.  They seem to be great with more than one in a party.

Ranger is a great solo guild with a decent amount of flavor.  For some reason
they seem to not be in demand in parties - which is odd to me as they do have
decent regen and offensive abilitites with some defense.  Ranger quests
certainly make the guild more fun.

I think I am going to reinc again soon to get another guild experience.