Or I guess this is pretty obvious but just ask people in your FC if they have any alts they would like to level with you. If any of them are working on a tank or healer, things would go a lot faster! You could even try putting up a leveling party on party finder and spam a certain dungeon. Maybe people would bite, but I'm not sure.... Alternatively, although I know everyone is probably sick of hearing it, make a tank/healer friend and ask for help!