In this game you really want to balance between the mitigation stats since all of them are bound pretty strictly.

Yeah, Immortal is the key for a tanking build and Crushing Blow is really important. There are skills you can skip in the tree, but not that one.

This ^^^ and make sure your team understands they should be working in the opposite direction and designate CC targets where possible.

It does allow Savage Kick, but it does not generate threat. It is a middle of the road skill for me, but I do use it in PvP and PvE.

This ^^^ and I am almost full Immortal spec with a few points in the Vengeance tree.

1. GW1 2. Early UO 3. DSO

Cross server PvP would greatly improve the quantity and quality of PvP. I don't believe there is such a thing as community when we're talking about purely instanced PvP and if you're remembering names of random people then we're really playing in a very small pool. Open World PvP is where community, alliances, and guilds matter. Instanced PvP is for small teams/individuals to hopefully get matched up with similarly skilled opponents.

I run Quinn 99% of the time because I prefer to move quickly from one fight to the next without down time. He also puts out decent damage (when properly geared) even in his healer stance.