I would love to see FR DURING the spellplague. Magic is dangerous and explosive... sometimes even deadly. The veil between material and etherial is shaky and unstable. Strange things poor out of the aether or dissapear into it. Everyone is frightened, panicked, and otherwise scarred of the future and what it might hold.
Because of the death of a god, all faith is shaken and worship is becomming less common. New gods rise and fall like heroes in a dungeon crawl, and devine magic hold a higher place of respect within Faerun.
Generally I'd make Forgotten Realms a world of chaotic magic, random astral and magical events, The "names" of the realms wouldn't be there because they are dealing with all the BIG crap coming into the world and tearing reality apart. It would be a world of strange new monsters, Living spells, corrupting magics, and all arround excitement and intrigue.