PLD no flash?

[Reynhart]

We can have diversity when we stop having Savage and Ultimate content.

For me, that's irrelevant. Any party composition can do any content. If you want to play optimally, just group with people with the same mindset in a premade.
There are lots of people that play jobs that they like, and do those content in a completely non-competitive way and, thus, don't give a damn about being "meta".

Also, removing any sense of identity will just make jobs feel more bland for the extreme majority that don't even set foot in Savage or Ultimate.

That's why I think the game could support job customization. If I want to play seriously, I will dedicate one job to be my raid job, that will most likely follow an optimal build. And for my other jobs, I'll be creative so that they still feel fun to me.