I have many alts for roleplay purposes and getting them to 50 is just so they have access to all gear for glamouring. I do have a level 50 tank with this method. Making an alt makes it less boring to grind up a different classes because you still have quests to do and aren't just grinding repeatable leve quests or fates or dungeons. You also don't have to pay more than you are to get fantasias to swap things around if you find you don't like something.