The events which concern me are (Possible spoilers?):
Spoiler
The Civil War (Stormcloak or Imperial Victory, death of either Ulfric or Tullius, different Jarls)
The Dark Brotherhood questline (Emperor dies)
Azura Daedric quest (Black Star could be created)
Dawnguard Questline (Vampire or Dawnguard victory)
The Aetherium Forge quest (Creation of an Aetherial artifact, three possibilities)
Main Quest (possible death of Paarthurnax)
The Civil War (Stormcloak or Imperial Victory, death of either Ulfric or Tullius, different Jarls)
The Dark Brotherhood questline (Emperor dies)
Azura Daedric quest (Black Star could be created)
Dawnguard Questline (Vampire or Dawnguard victory)
The Aetherium Forge quest (Creation of an Aetherial artifact, three possibilities)
Main Quest (possible death of Paarthurnax)