I'm not opposed to a villain land with the correct selection of villains, but I haven't seen a pitch that's more than 'all these villains are sitting next to each other and chilling out with rides'.
Disney doesn't really do catch-alls anymore in WDW, outside of AK because it doesn't really support single-franchise lands unless you are the Highest Grossing and 3rd Highest Grossing Film of All Time. And even then that's the smartest move to do with the main goal with the land. I doubt we'd ever get another thing like Frontierland where there's several IPs/different characters living side by side.
I do really love your latter idea though, I can see a Nightmare Before Christmas mini-land featuring the iconic spiral hill with a dark ride, I can see something with another villain (I wanna say Scar would be the most likely because the Elephant Graveyard would look nice next to NBC-area) and Davy Jones clicks well with me also. He's a villain the general public still talks about (thanks to his AMAZING VFX) and would be stunning with a good AA. While that'd be two Pirates attractions in one park, I feel both would seek out different goals.
Plus? He just looks cool, a peg leg AND a crab arm? Sickkkkkk.