I've been tanking with my 115 champion lately (Galynna), and was asked about the traits she uses. In case anyone else is working to build a "chank", here's some info about how I have her set up. Caveat: this is a fairly new attempt and my setup is not necessarily ideal! :-D
Galynna's traits and threat skills
I generally only use my blue line if I'm tanking in a 6-man or 12-man instance, and sometimes in the bosses of 3-man, depending on my 2 fellows and the difficulty of the run in general. Blue-line offers greater threat generation, and increased survivability. I am considering dropping some of the later blue-line trait points to put more into yellow-line for increased damage because a good yellow-line champ, and occasionally a red-line hunter, will pull aggro off of me right now.
Galynna's gear and LIs
You'll notice there are 2 pocket items; I believe swapping to the bell will increase the damage I can do, I just haven't gotten around to it because life's been busy.
Fully decked out in her current blue-line build, gear, and LIs, Galynna's stats are pretty tank-like. She actually seems to be very survivable so far, although other than 3-mans she's only off-tanked T1 Abyss and solo tanked Bells of Dale T2C. As I said, the greatest challenge has been holding aggro against early-hitting, heavy-hitting hunters and champs. Given a hit or two to get ahead she seems to do OK although I'm still tweaking my skill rotation for that.