Quote Originally Posted by Segev View Post
I do not see "enables the build" to be "a build tax" if the build is not the only viable build, or the only viable way to use the thing that the build centers around. If hex is useful without building around it, then a thing that enables a build around it isn't a tax, because it's not a tax to use hex. Does that reasoning make sense?
You can still use eldritch blast without agonizing blast, it still has plenty of value as a d10 long range damaging cantrip with a very good damage type. But Agonizing blast is such a low cost, high reward improvement that even if you're not building towards that kind of caster, it's hard not to pick it up anyway.

That hex feat isn't quite in the same territory...but it's getting there. One of the main reasons you might not pick to use Hex (or at least trade it out later) is that getting the full value out of longer versions of Hex means holding back on other concentration spells. But removing that cost means those other builds suddenly are only a invocation away from getting the value out of hex on top of the stuff they were already doing. OF course, the spell slot cost (depending on how the group does rests, may or may not be an issue) and concentration dropping issues are also things to consider, so it's not quite an auto-pick, but still.