this is my snb build
For 2 chosen groups I'll drop stagger and grab heal debuff. I'm geared, so I don't find oppression necessary, you might until you get inv+ though.
Edit:for lowbie RR, I'd drop the stagger entirely. KD is super important, and AP aura is pretty mandatory. Just put whatever points you can into right tree for resis aura.
Talis I use wounds to cap(1050) and then toughness.
Aura wise I run AP/tough/resis on SnB. But swap out toughness for whatever the group needs.
Morale pump is your main advantage for snb, so use it. Quick M3 bellow or save for m4 ID. Use your Challenge on CD, swap guard as needed, punt tanks, use Hold The Line to protect from Rdps, and set an assist macro. You'll do fine.
RR wise is a little tough. Max block, then either Trivial Blows or -crit%. I prefer TB alongside -10% crit damage liniment(which also gives some more regen)for 50% less crit damage. I put the rest in parry and dodge/disrupt. Try out different builds though, you'll find what you like.
Also, if you don't have them yet, download the add-ons Tether, Enemy, SwiftAssist and Buffhead.
Gl