I would want the next Elder Scrolls to have a lot more variety.
It has a huge open world environment that takes a long, long time to explore. Had a nice variety of creatures to do battle with.
What I would want in another Elder Scolls are two things.
More and different creatures underground. Plenty of caves and dungeons to check out for fun and pleasure.
The problem here is Skyrim basically had three things (other than humans) in dungeons to fight. Usually it was Draugr. Occasionally the Dwarven Automatons and/or Falmer would be there. Rarely anything else.
That was basically it. How about some goblins, minotaurs, ogres, or something else once in a while to break up the same few groups of enemies?
Loot. Where was it? I quit opening chests about halfway through my playthrough since I had plenty of money by then. Useless weapons, gems/jewelery, or food is what was in most of the chests. I got the Mace of Molag Bal at level 14 and never used anything else. I didn't 'feel' anything was better. Best armor in game was crafted...so why loot anything? Nothing that would be an upgrade.
Looting is half the fun of an RPG to me.