I am only lv 54 ...... I would expect this if I was at level 81 but at 54.
I'll ignore the "ok, so you Super Ultra Monster MinMax Powergamed your character" comments, they've been covered.
I'll just talk about what I've quoted above. Something you might like to know -
the game is balanced around hitting level 50 as a "high level" character. The world and enemy scaling stops there. So at level 54, you're already above the game's power curve. At 81, you'd be way, way, way beyond it.
This is mostly because of the way the character leveling works - you can only hit lv81 with every skill at 100. Since most "normal" characters won't have nearly that many skills extensively used, the game isn't balanced around level 81. It's just there for completeness.
(I haven't tested it myself, but I'm presuming that if you followed what would be a "class" in earlier games, a set of about 6 "major" skills, you'd hit level 50 with those skills around 100. I didn't, but then I played more of a generalist character - I've got around 10 skills that I use alot. This gives me a few more levels above 50 if I were to max them out. I haven't yet - only got my first skill to 100 at level 48. That was Smithing.)