This could be a futile discussion, but I haven't seen a discussion specifically centered around this topic yet. Link me to one if I'm mistaken.
So with all the interviews floating around it is more or less confirmed that Jobs will share the level with the respective class it is associated with. There are a lot of players who already have level 50s and even as someone who only has 2.5 50s I feel that Jobs should have thier own EXP bar. In fact I would like it if Jobs had an even steeper EXP curve than the classes did.
Why?
1. Something to do. People with all 50s will simply have a couple quests to do and then they will once again be maxed out on everything they can level. If Jobs had their own EXP bar it technically gives them 7 more classes to level up to 50 and therefore more stuff to do in between patches.
2. Specialization. When leveling a class there are two or three kinds of mindsets: a) I love this class, I want to get it to 50 and spend lots of time with it. b) I want to level this class to 50 just for versatility, but I don't really like it. c) I don't like this class but everything else is 50 so I may as well be a completionist. For people who really love a particular class and want that to be their specialty could then devote the extra time to leveling the Job of that class to 50. Someone who wants to have CNJ up just to heal if needbe could still do so. But for someone who really likes healing, they could strive to achieve 50 WHM.
3. Diversity. Similar to point #1, and this came up in the crafting cap discussion as well. The issue is that especially for new players once they get to 50 theres a lessened feeling of accomplishment because everyone else has that class 50 and then some. By making jobs have their own EXP then that new player could take GLA to 50, and then PLD to 50 and feel like they stand out from the masses.
4. EXP is very easy to get. Under the current system it is not unreasonable for even a brand new player to go from 1 to 50 in under a month, weeks even. This kind of rapid growth is good because it allows new players to reach endgame content quickly. However, since Jobs will be superior for this kind of content it will allow players to get their feet wet in this content and determine if their chosen class is truly what they want to be. If so they can devote the next 2-3 months (Yoshi's timeline) to getting the Job of that class to 50 so that they can then participate with experienced players on their respective Job while already knowing how to play that role from their 50 class.
5. Feeling of accomplishment. Classes already have a three layer quest system that allows players to get a little more into the story of their class. Adding the job quests every 5 levels would feel a little out of place to me because you are getting the lore for two separate loosely connect stories at the same time. It would be better to get the class to 50, having done all your quests and be able to say "Okay, I'm ready to take this to the next level". Also for all the people already 50, it will simply be a matter of doing quest A B C D E, "k got all this class' gear, next".
tl;dr, I know. But thank you for taking the time to read all of that if you chose to. Now then, since you all just absolutely love "like polls", here goes.
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Like this post if you feel Jobs SHOULD have their own EXP separate from classes