Any reason to NOT choose a job?

[Tupsi]

Maybe THM?
Exact same rotation as BLM, while THM can use Internal Release and Blood for Blood.

..Meanwhile you'll have a larger permanent boost if you were to go as BLM instead of THM

[Ri_ri]

..Meanwhile you'll have a larger permanent boost if you were to go as BLM instead of THM

Yeah, you're right

You can use THM to spam Flash in FATEs, though!

[Alyko]

Yeah, you're right

You can use THM to spam Flash in FATEs, though!

Pretty much this. With some FATES lasting less than fifteen seconds, I stay on archer to spam Flash.

[Clavaat]

..Meanwhile you'll have a larger permanent boost if you were to go as BLM instead of THM

That's not necessarily true. People have been looking into the amount of damage increases INT gives and frankly, +20INT will only give you about +10 dmg per attack, probably a bit less. The true test comes as to whether or not the abilities you use will give you enough burst damage to compensate, and also if there actually is a cap for damage bonus gained from attributes. I'm not saying it's one way or another but I definitely think there are aspects worth looking into, besides assuming some attributes should be the main and only focus. I'd be really curious to see some of the combos. Besides, as I said before, its possible, not proven, that survivability may actually increase with access to some other abilities.