Having played most of the FF series I'm used to the idea of advanced jobs unlocking later, and I do understand how entangled the HW jobs and lore are with ishgard so I know it's unlikely anything will be changed. But I do see the OP's point. I have a main who does everything, but I also make some alts that are focused on one theme or just one job. I pick their race/look/everything based on them being that job. And as more and more jobs get added to the game, the ones you can actually start with and play through the whole story as becomes a smaller percentage. Heck, I deleted a pure healer alt that was level 60 because the 20levels of blm she had back when you needed it for swiftcast kept bugging me ;)
So it would be nice if there was some way to give the option to pick up some of those jobs at the beginning and just have them quest free until you reach the point they'd normally unlock, as a poster above said. I don't expect any change, it's just a 'would be nice' sort of deal for me.
However since rogue is now a lvl 1 class like any other, I really think that one at least should be added to character creation. The quest to pick it up can be left in game for those who didn't start as one, but there's no real reason to keep it out.
As for the HW jobs, it would be cool if there was an npc 'smuggler' or something in western coerthas that could smuggle you into a different instance of ishgard city at level 30, where the only quests are the job ones. I don't remember if the job quests for those jobs had any references to ishgard story or not that wouldn't make sense lore wise if they did allow it. But since they are lvl 30 jobs, would be nice to be able to get them at 30.