I realize that this stat was added to allow tanks to scale up their enmity production in order to keep up with damage dealer gear progress, however, the current implementation is problematic for a few reasons:

1) Tanks are forced to choose between survival, or "tankyness", and the ability to hold hate. I don't think this is a choice most players particularly like to make. Currently all content favours focusing on holding hate because rewards are based on speed (AV, CC), defense isn't needed (Ifrit, Moogle), or because slow and steady makes things harder, not easier (Garuda).

2) +/- Enmity does nothing at all in PVP or other potential future content where hate mechanics are suppressed (such as a boss that completely ignores enmity).

3) As tank gear progression is split between survivability and increased enmity generation, in the long run tank enmity probably cannot keep up with DD gear progression anyway, as for them the sole purpose of every upgrade is to further increase damage output.

I would propose that abilities like Flash and Provoke scale based on one or more defensive stats, like Defense or their primary and secondary attributes. That way tanks can focus on simply being tanks. This would be similar to how WoW solves the problem.