Update: Some other classes assume the actor origin is in the middle of the capsule. It’s mostly the AI stuff. The main problem right now is that UNavMovementComponent::GetActorFeetLocation isn’t virtual. I had to edit the source to override it. It’s interesting though, I’m just doing this for completion. My game did not have any noticeable effect when using the original functionality. My players and AI all work the same as they did with the original components.
Also worth noting that using this ground-based origin, my code got a lot cleaner. I honestly can’t imagine why anyone would have started with the capsule-center origin method in the first place. It takes extra work to accommodate it.