So I was working on rebuilding an old character of mine, and picked up Supernatural Charm. And then I went back and thought about it.
It's always going to be a 1st-level charm. And it has the incapacitation trait.
And you can first take it at level 5.
Isn't it going to be useless in the vast majority of situations you find yourself in, even at the level you pick it up? And it's only going to get worse from there. In order to get good use out of it, the target really has to be level 2 or lower.
The charisma apex item has the same problem.
Not a problem that I can see. For Apex item:
Assume expert will for a level 14 (double or more above a 4th level incapacitate spell) adversary. That's +18 without wisdom modifiers.
DC 38 (apex item)-18= 10 or lower on the d20 to critically fail (thus a regular failure). That means a level 14 adversary would have about a 50% chance to fail, which isn't that unreasonable for potentially removing someone from a fight or taking away their agency. If they have master or better proficiency in Will, you shouldn't be targeting them.
As a 1st level innate spell (equivalent to a gnome's speak with animals 1/day from P1), would you really expect it to be an encounter ending effect?
It's amazingly useful when dealing with nameless NPCs to get information/better results, especially for someone who isn't a spell caster. It's moderately useful against adversaries lower than your level.