Wow, you're really good at drawing! -jealousy-
What I always find when I'm trying to come up with a character concept is that I already subconciously know what kind of character they are. I also draw my characters (but none of my drawings are half as good as yours!) and when I do I normally kind find out about their character from the expression I draw them with and the kind of hairstyle I give them, as well as the name I eventually choose.
For example, the beautiful bust you drew. Ahren Pyralis. That name sounds passionate (fire) and elegant (eagle). It has a slightly exotic tang to it.
His expression is almost smiling, but his eyes seem almost disdainful or squinting against bright sunlight (or maybe I just suck at interpreting pictures. Please forgive me if I'm horribly wrong!). The angle of the eyebrow to the left is raised, like he's amused at something and smirking at it. What this tells us about his potential character, based solely on the picture (and my crappy interpretation of it): he's an outdoorsy type (sunlight) who has a good sense of humour. He's really handsome and, by the looks of things, he knows it and isn't afraid to show off.
Oh well. I suck at this. I hope that helped. In a true movie maxim kind of saying, the answer lies within. ^.^
Good luck!
-Max