I am simply going to jump in on the topic "I look at gear to determine class". I personally know that I am up against a mage because I am getting a frostball in my ass, or because my UI shows me a blue healthbar. Addons, unique weapons and unique spells will tell you more than enough. I embrace this feature. Also, we have know idea if there will actually be such a gap between the looks of "light" and "heavy" armor.