In 1e, every DM was expected to create their own setting with its own flavor.
I wish that stayed.
3. I prefer paladins to be as in AD&D, when they fit what inspired the class. None of this evil/bad paladin stuff as a generic accepted class
With you on this. I will never play a paladin that isn’t LG. Murderhobo paladins are like nails on a chalkboard for me.
Then the anti-paladin showed up in a Dragon magazine and suddenly everyone wanted to say "screw the role playing requirements, I want all that power and to be able to not follow any rules." Nevermind that the anti-paladin was never meant to be played by players...
Primal power as distinct from arcane or divine.
Each setting having a self-contained cosmology, with the meta-settings having the option to intrude but only from their own point of view (I could see a Planescape or Spelljammer supplement including Eberron stuff. I don't want Eberron to include Planescape or Spelljammer stuff.)

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.