As I've been working on Advanced Edition Characters for Labyrinth Lord, I've been thinking a bit about the cosmology. I want to stick with the forces of law and chaos as the major axes or philosophical underpinings, with concepts of good and evil being ways in which law or chaos may be executed, but not major spheres of philosophy per se. I think this remains true to the pulp literature origins of gaming. So even though AEC will allow good and evil to be added to alignment, they should be interpreted as more organic than law vs. chaos.
So, all of this is leading to how to organize the planes of existence. I want to get away from the complexity, but also sort of bloated cosmology that was in 1e. If you are familiar with the second issue of the Scribe of Orcus, I outlined the basics of one possible scheme for the planes, which I will probably adopt for AEC. I made a two-dimensional representation of the planes that will likely appear in AEC in some form. Here is the rough draft for those curious: