It is natural to progress in power. When you find a better weapon, unless it is a conscious RP decision, you equip it. When you level up, it is natural to get the Perk that has the biggest advantage to your character you are building.
The key here is in that each person has different ideas about what perk is the best choice at any particular time. I stopped getting upper level perks in some skills because I thought they sounded boring. Someone else might see them as a "natural progression of power".
I think in order to be overpowered you need to go out of your way to do so, not just take certain Perks or wear certain items. When I say overpowered, I mean completely out of scale with the game. You obtain that by just doing things normally.

I felt like I had decent challenge (bosses I ran into could kick my butt, or at least do appreciable damage, etc) up into the 40's. On Adept. I didn't start to feel "overpowered" until I got into the 50's, after the MQ and Civil War.
If you disagree that I am not doing things normally, I do not know what to tell you.
I don't disagree that you're doing things normally by your standards. I'm just saying that not everyone's "normal" is the same.
Really, you would need to make absolutely idiotic decisions to not be too powerful in this game. It is a misnomer to say that you are not "powergaming". That isn't not powergaming, it is just putting Perk points in haphazardly.
Well, I thought that my perk choices were good. I certainly didn't do it randomly or haphazardly. But I'm sure someone who's into pure efficiency or max power would see my choices and my reasoning for them when I picked them, and want to bang their head against the wall at how terribly I'm playing. (I certainly had people say negative things about my preferred talent builds in World of Warcraft. They certainly weren't anything like the "approved" ones that everyone said you had to follow.

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I believe http://skyrimcalculator.com/#58467
I think the only 100 level skill was Smithing (reached that at lv48). One handed and Light armor were in the low-mid 90's.