Want to play meta? Pick the flavour.
Want to play, fullstop? Pick what appeals to you.

Unless you're partaking in progression right out of a content gate, one shouldn't over-think it too much, especially when MMORPGs are all about periodic changes and tweaks that shake things up once in a while. As it stands, PLD is still the mitigation king, Warrior is still the deeps-king, and Dark is still the third-wheel king - which isn't saying it can't do its job well, only that the other two just happen to be slightly better in X or Y way.