I do not think that this will be errata'd as there is no real benefit from doing it. Most heroes are interesting because of their abilities and not because of their stats. In my opinion it works like it was intended to do.
Witch Hag's Curse/Cold One Chariot
That's a good point. I wouldn't be concerned about two heroes with blank text either.
I'd like a blanked Tyrus Gorman.
I was wrong about this. Witch Hags Curse just blanks the restriction, but leaves the Hero keyword.
From Lukas at FFG:
Q. Is "Limit one Hero per zone" a clarification of what the Hero trait means, or actual rules text on the cards? i.e., would it be blanked by Witch Hag's Curse, which wipes out everything but Traits.
A. ”Limit one Hero per zone” is actual rules text on the card. Traits are passive, and cannot contain any rules in and of themselves. So if you blank a hero’s text box with the Curse, then it loses the limitation (but not the Trait). However, any other hero played into that zone would still carry the limitation, so the only way to get two of them in a zone with the Curse would be to move a second hero with it already attached into the same zone.