Firstly, I do not seek to promote havoc, flamewars or any such stuff like that, and I personally doubt that this will have any effect, it was simply something I felt I had to get off my chest. Why, beyond the fact that it's so disconnected from the cosmology of old, is 4e's cosmology such a terrible thing?
Is it because the Upper Planes are now "Dominions" in the Astral Sea instead of seperate, infinite planes of their own? Is standing at the base of a mountain that stretches further into the sky than your eyes can follow really that much less fantastical if you were seeing it contained within a crystal orb barely twice the size of your fist a heartbeat ago?
Is it because the Elemental Planes & Demiplanes are all one plane now? Is a city the size of a mountain range composed, down to its populace, entirely of living ice really lessened in its impressiveness by the fact that a garden of island-sized flowers is currently drifting past on the winds in the sky above?
Why is Sigil less than it was if it goes from being the literal center of everything to the effective center of everything? From sitting atop an infinitely tall mountain at the center of the Plane of True Neutral to being the place where all parts of the multiverse touch simultaneously? Becoming a place where genasi rub shoulders with shadar-kai, where orcs, dwarves and elves debate philosphy, where companies of angels gather to recoup their strength after losses in battle, where devils seek to entice mortals into serving in the endlessly warring armies of this devil or that, where demon seek the portal to their next target, and where pilgrims gather to seek the doorway to the home of their god?
to me it's kinda dull, uninspiring, too much black and white, most gods in one place, floating
one thing that I included in homebrew cosmology, is Shadowfel, just the name