Well, I have a few ideas.
One would be to have two specific areas designated for fighting.
One area were anyone can gather and fight in a free for all style, like outside Willow's Shop in Marind Bell.
The other area would be for fighting that is pre-agreed only. So you go in and then ask if people want to engage in a fight. The key is that this rule is enforced and if people just wander in and start attacking players without asking, then they are punished (perhaps by other high level/rpc characters attacking them).
This area would have to be a little off the beaten track though to reduce the appearance of wandering players who are 'ignorant' to this rule.
This would be a great place for healing rits and spells and for players levelling up creatures.
As for a specific role for myself, I'm not sure. I'm open to suggestions.
Roles that would be good for the alliance in general would be healers, enforcers (to enforce the non combat area rule or whatever is needed) and scouts.
Given that the Alliance is meant to protect the forest and land it should maybe have an intelligence/scouting force to report on activities and potential threats outside the forest. Maybe even a team of assassins/saboteurs to deal with threats before they can directly affect Loreroot. I mean you don't wait until a mob of people with big firey torchs enter the forest before you decide to do something about it.
Just a few ideas bounding around my head at the moment.