Are there any differences between Skyrim & Skyrim: Special Edition?

What are the major differences between Skyrim and Skyrim: Special Edition? I'm looking to understand all of the signficant changes between Skyrim and Skyrim: SE; not just whether or not a few quests have been changed or not.

Specifically looking for:

  • Graphical improvements?
  • Gameplay improvements?
  • Performance improvements?
  • Mechanic impromvements?
  • Modding improvements?

Mechanics

  • Save games are now sorted by character, Fallout 4-esque

Graphics

  • Supports 64-bit render targets by switching from 32-bit to 64-bit
  • Options to enable God Rays, Snow Shaders, Lens Flares
  • Supports Direct X 11

Modding

  • Console versions now fully support Mods