Ranked is only for max level characters.
Firstly, you said in a previous post that you'll be keeping the 10-29, 30-54 and 55 brackets for Arenas. How will this work in terms of Ranked matches? Will the 10-29 and 30-54 brackets be considered "Non-Ranked" Arenas or will sub-55 players now be able to participate in Ranked?
Role is determined by your characters current specialization in the Skill Tree.
Secondly, how will a player's role be determined? Is it going to be a system similar to Group Finder, where you declare your role? Or will it be based off of Skill Tree distribution, gear, stances when applicable, etc.? I only ask since I can think of some hybrid instances when someone heavily invested in a Damage tree could actually be geared and "stanced" for Tanking. E.g. Defense/Vigilance hybrid.
You can join the Warzone queue to participate in them both.
Finally, can we queue for both 4v4 Arenas and regular 8v8 Warzones (non-Ranked) at the same time or do we need to choose one or the other?