Whoa, this thread is very much alive and kicking!
I'm digging the Tribes although I'm sticking to Random select because I think it's important to figure out strategies to defeat them. I'm not sure if it's a bug or not but the Tribes' spiked armor doesn't appear to do any damage to Elves which is a huge detriment.
Otherwise, it seems like the Tribes are the strongest overall team because they have so many ways to disrupt formations and so many attack boosters that your buffed troops are rarely, if ever, truly safe. As I have far too much respect for all of the players here, I'll refrain from posting my personal strategies although many of you can already tell what my general style is like.
EDIT: Just read Pastry's post. That makes complete sense and I never thought about that.