I feel I need to say that hex is interesting, and cursed is somewhat interesting, but they really shouldn't be in the same set in their current forms. Because cursed cares about -1/-1 counters, and hex gives things -1/-1 UEOT. Lots of players will think that hex will trigger cursed when it doesn't; and lots more players will get annoyed that these two similar things don't actually interact.

I actually thought about that. I felt that to bestow the -1/-1 counter I'd probably need to include some kind of mana cost as well, making it something like Outlast, which is what pushed me away from that direction.

I think hex is interesting, but as Alex said, I'd rather see it grant a counter. In fact, I would rather turn it into a keyword action. Then you could have a creature with ": Hex target creature," a sorcery with "Hex target creature, then draw a card," and an enchantment with "Whenever a creature becomes hexed, it's controller loses 1 life."
Brainstorming here: maybe change hex even further. ": Hex. (Put a -1/-1 counter on target creature without a -1/-1 counter on it.)" Could that be an option? It would interact nicely with my suggestion for cursed, and also make the power level of adding a counter a bit more acceptable.

I do like the clause of the second suggestion, though I don't feel keen on Hex being an ability word. I miss out on some design space, as a sorcery or instant in the style you suggest wouldn't work (the enchantment still would).

Why not? It would be just life Populate our proliferate. See Wake the Reflections and Tezzeret's Gambit.

I simply want hex to be tied to coming from a creature.

Oh, fair enough. What design space do you miss out on by making hex a keyword action (I used the wrong term before). I'm just curious here, and not trying to seem critical.

You can't have a hex lord if it's not a keyword. That's all I can think of. The current reminder text shouldn't say "this creature has"; it's already printed on the card.