I have quite a few hours in but I'm not sure how you guys with 80+ in one playthrough do it. Even without grinding through smithing/enchanting, by the time I was lvl 39 I was so powerful that exploring and combat had lost any kind of tension or interest. I would walk through room in a dungeon and try to aggro as many as I could and then kill them all with just a few shots without losing much health. It's frustrating because exploration is the best part of the game. I turned the difficulty all the way up, but it didn't help much.
Don't get me wrong; I want the reward of feeling powerful after investing the the time and effort to build my character, but there still needs to be some challenge left somewhere.