Dark Sun, Midnight, Iron Kingdoms, even Spelljammer are examples of things I'd like to see more of.
I want me a
Planescape campaign that doesn't worry about the Great Wheel, that's heavily centered in Sigil, that embraces some of the Victorian steampunk/spellpunk atmosphere, and that is in love with exploration and possibility.
In fact, this is likely going to be my first 4e game.
But I agree. And I agree with Ruin Explorer, too, that the various 'cultural splats,' while EXCELLENT, aren't really totally fresh. I'd like to see them integrated wierdly into other settings -- a Nyambe as a part of Dark Sun, an Oriental people as part of Iron Kingdoms, a colonial Northern Crown feeling for Spelljammer...I could groove on that.
Still, I need basic cultural splats for homebrew goodness, so I'd like 'vanilla' Nyambe/Northern Crown/OA, too.
And I *definately* don't want them linked to FR, so no Kara-Tur, no Al Quadim, no Maztica.
But YES Oriental, Arabian, and Mayan campaigns!