In vanilla oblivion, I had no strategy. I would simply Kill, and heal because it was so easy to do so.
In a modded Oblivion using Oscuro's Oblivion Overhaul, I'd use my surroundings to my advantage. It was also very handy if your character had extra items like potions and knew how to use ranged and melee weapons. The enemies were much stronger and boss NPCs did exist.
In Morrowind, it kinda worked backwards. There was a lot of strategy at the beginning of the game and it slowly became easier. You had to pack a lot of potions, you needed to figure out how you were gonna level your primary skills so you don't end up toe to toe in a hit in and miss match with an orc with a warhhammer.
I can't remember how much strategy was involved in Daggerfall. I think the only strategy involved for me was estimating out the travel time for quests. (Should I take a ship, horse, foot etc...)
As for my likes for this strategy aspect, I believe it lengthens the game and makes everything you accomplish more worth it.