First, there isnt a right answer here. All are viable. Every primary has an unique attribute. Ele is energy storage, meaning a larger energy pool than other classes. The prob with warrior and to a less extent ranger is limited energy pool. Ranger is expertise which reduces the energy cost of ranger spells. Also it should be said that after you reach level 20 you can change your secendary class. Right now air elementalists own tombs but im sure thats the flavor of the month and will change as more groups counter there build, they are glass cannons and mesmer is a real good caster killer. The group/guild build is really more important in the end game than the indivisual.