The Great Wheel.
I hated that.
The inner plane/outer plane distinction I can handle, and have used in my own (Rolemaster) games. But I have no real use for a seperate Astral and Ethereal plane.*breaks out the popcorn and awaits*
As for the outer planes, I've treated them 4e style well before 4e started too, because the "wheel" makes no sense once you get rid of alignment - and then you can go for various sorts of thematic and pantheonic outer planes rather than the weird scattering of pantheons over planes that we've seen ever since the original DDG and the MotP.