I like to get to lvl 6 and 220% xp, you can't go over lvl 6 on the Island. This gives you a chance to do all the quests on the Island, harvest resources and practice tradeskills. You can also get a few recipe books from killing mobs as well.
As soon as you do your citizenship in your chosen city, you will ding twice and being well equiped with all the quest items from the Isle.
Aammer