I think they should just release Vanilla as it was, despite its flaws.
It's like going back and playing the old NES Zelda games. There are a lot of things in those games that are confusing and unfair. Dungeon entrances are in super random places that you pretty much need a walkthrough to find. Screens of bullet hell are very common, even way before you have enough health that you can take some hits before falling over dead. The fairy spell in Zelda 2 can softlock your game when used as intended.
Despite the list of problems, some of us still like to go back and play through those games and experience them as they were. If Nintendo re-released Zelda 2 but also re-balanced the game for a modern audience and added Fi in to tell you where to go, it wouldn't be Zelda 2 anymore. Fans who want to experience the original would emulate the original version instead.
I think we can all agree that there were a lot of bad ideas that made it into Classic WoW, but they still shouldn't patch those things out of the game for the sake of player convenience