As shown in the spec progression links I posted, that's exactly what I'm doing - first going for 6 Justicar, then going for Inquisitor Aggressive Renewal. However, after that I'd like to reach spam status on Tyranny asap.
Your final spec you posted is very hard to argue against, and I'm switching to that too for level 50. :) I just regret not having the "Dark Harbor" buff - since it stacks with the Shaman resistance buff it could be pretty uber.
After talking to people on my server, I think I'll keep the tank role at 40 Justicar for now and see what heppens. The cleric tanks there say it would be a great spec and that they love the Shaman "Jolt" spell for Justicar tanking.
Note that I didn't mean that the Shaman wisdom buff would be to primarily boost the tank - it's meant for the whole group since everyone is Wisdom-based. Basically a 5x factor on that one.
I'm now looking at this progression:
Level 10: 7 Inquisitor, 0 Cabalist, 6 Justicar:
http://rift.zam.com/en/stc.html?t=10rod.V0z..g
Level 20: 14 Inquisitor, 6 Cabalist, 6 Justicar:
http://rift.zam.com/en/stc.html?t=10rod.V0z.V0z.Eoob
Level 30: 14 Inquisitor, 20 Cabalist, 6 Justicar:
http://rift.zam.com/en/stc.html?t=10rod.V0z.V0VVx.Eoob
Level 40: 22 Inquisitor, 20 Cabalist, 11 Justicar:
http://rift.zam.com/en/stc.html?t=10....V0VVx.Exobboo
Level 50: 35 Inquisitor, 20 Cabalist, 11 Justicar:
http://rift.zam.com/en/stc.html?t=10...V0VVx.Exobxxoq