A lot of people in this thread have noted the random/swingy nature of the Hexes, and that they seem "more bad" than the Boons are good. I agree that the randomness can make them a bit annoying to defend against or plan around, however, I do have to commend Donald X. on designing the Doom cards (that we've seen so far) carefully so that excessive Hexing is usually tricky to pull off:
With two of the Doom cards, players themselves control when or if they get Hexed (Cursed Village and Leprechaun). Skulk Hexes other players but it’s a terminal stop card that gains another stop card, so playing several in succession is very difficult. It is possible for Werewolf to hand out Hexes quite rapidly, but it’s dual nature frequently tempts players to use it as a Smithy instead, especially if it's the only draw on the board. Unlike something like Cultist which can very quickly ruin other players’ decks, I don’t think we’ve seen any overly oppressive Doom cards.
While there certainly is potential of unfortunately swingy moments with Hexes, I don’t think any of them will be overbearing. I’ve been impressed with how intuitive the Nocturne mechanics introduced so far are, and I think Hexes will actually be kind of fun and interesting most of the time—more fun than Ruins anyway.
P.S. I just played a game where my opponent bought a Cursed Village after drawing their deck, only to have Locusts immediately trash it. Obviously, that doesn’t happen every time, but hey that sure did give us a laugh.