Not sure which thread will survive, so replying to both of them
I can see the perspective of the Barbarian being of nature, embodying it in a way that could be said a Paladin embodies the precepts of the Divine. That makes sense to me.
Honestly, this has got to be one of my favorite subclasses thematically, the idea of calling upon your ancestors to aid you in battle is immensely cool.
I'm actually playing a Knight Background Ancestral Guardians Barbarian at the moment (do the ancestors stop protecting you if you still honor them and remember the correct rites? I say Nay and the clan has been blessed by our ancestors for a long, long time, even if we know are knights for a noble family), we just hit level 6 last week, so I'll finally get to use that Spirit Shield ability, but I've found that the level 3 ability hasn't come up much.
I generally end up in my own special knot of bad guys, so the enemies I'm attacking are already beating on me, so the penalties to hit my allies have come up I believe exactly once, maybe twice.
Still, this is one I'm excited to see.