What was once Eldre'thalas, now Dire Maul
To accommodate for the loss of the Well of Eternity, Prince Tortheldrin bound the demon Immol'thar so that it could be drained of its power. However, as time went on, the demon's power waned. In order to preserve what precious energy it had left, Tortheldrin and his loyal Shen'dralar killed many of the people still living in Eldre'thalas.
How a player starts could be 1 of 2 ways (either one I have lots of quest ideas for). Idea #1 is that they are Highborne that are breaking away from the Shen'dralar after the atrocities were committed. Idea #2 is that they are surviving denizens of Eldre'thalas, both high and lowborn. Regardless, as practitioners of magic with a dangerous history, they would be the only group starting out as unfriendly with Darnassus (not hostile, but unfriendly). They would have to progress through their unique questline to earn the basic trust of the Kaldorei. Their starting questline would end with them sort of zippering shut their questline by going to Darkshore (or some place like that), and then they would quest like any normal night elf would in that area.
I've embarrassed myself enough so I guess reach out to me if there're any questions? Rᴇɴᴀɴ#9267 on Discord.