Yes, mainly, though it can be used about women sometimes as well. Aesthetics is a matter of taste, but I'll tell you my views on this. "Komea nainen" in my opinion would be maybe a bit robust, tall, dashing and magnificent woman. Think of a real gorgeous battleship of a female person, like maybe Warrior Princess Xena. So a woman who's not traditionally femininely pretty and petite might be called "komea".
Yes, it's been used as a synonym for näyttävä (snazzy) but still implies that the viewer didn't focus on beauty because of other treats being more noticeable. I'd strongly recommend just sticking to kaunis or at least pairing the other word with it if you don't want to make the target of your words uncomfortable/confused. Also for me "komia" as a gentle sounding dialect word is more flexible whereas purely "komea" I'd never use to describe a woman.
Of course not. I'm just saying an English speaker wouldn't usually say Joni is always handsome. We might say Joni has always been handsome, because that is something that can change over time. But in the moment, in the present, a person is either handsome or not. That is my only point.