Which brings me to my question, when deciding armor for your characters, do you decide based on looks, armor rating, or a bit of both?
Looks.
Unless I find the armor rating puts me in a tight spot, in which case I resort to enchantments and smithing improvements and armor spells and perks. If that don't work, I go for the next best looking armor.
Looks for me, also. I don't know or care what my character's armor rating is, most of the time.
Looks as I usually roleplay more than stat-hunt. Most of my characters would find something like daedric as too odd to use.
Looks. There are a lot of ways to get the AR you want without choosing armor you don't like.
Looks.
Smithing and enchantments can make armor rating negligible or a non-issue altogether.
Rating until I get my [censored] together, and then looks
Seeing as how many of the higher-rated sets are, to me, not aesthetically pleasing to the eye, I prefer to stick with the lower-rated, yet more aesthetically-pleasing sets.
That's kind of my thoughts, too. Most of the "upper end" armors I do not find pleasing to look at. Looks for me, too
Both.
It has to look good and the parts should go together, but if I get a higher rated set that looks equally good I change.
In other words: I don't stick to leather the whole game just because it's leather.