Kyo is also a fairly practical guy. He usually doesn't like it when people decide to do what they want without considering other people. He demonstrates this pretty well whenever Ayame visits, taking advantage of Tohru's hospitality. He also reacts pretty humorously whenever Momiji, Kagura or Hatsuharu make outlandish suggestions. I'd hate to say that he has little in the way of imagination, but Kyo does tend to play the straight man quite often.
Working hard is also a feature that people don't really associate with Kyo. His classmates assume that he receives bad grades but he actually has no problem studying for long hours in order to exceed at his school exams. He also trains hard and enthusiastically at Kazuma's dojo, demonstrating a real passion for the martial arts. His passion goes as far as him taking on the ownership of a dojo after his high school graduation with the intent to take over for Kazuma once he retires.
On a lighter note, Kyo tends to be kind of ignorant of modern society. He doesn't know who Jason is, he's never seen dvds before, he has no real interest in girls at the beginning of school and he generally seems very old fashioned in the ways of technology. It's actually kind of endearing~
Sadly, depression is a major player in Kyo's life. His own mother committed suicide when he was around 4-5 years of age and his father outright blamed him for it and all but disowned him. While this seems like an emotional background for a manga character, there are people who suffer from serious mental health issues who have experienced the same tragedy. Kyo's mother loved him but his father's emotional abuse drove her over the edge. As a child, it was easy for Kyo to believe that his mother never really loved him at all if she chose suicide over him. Then to be blamed for it? It's unthinkable what kind of despair such a small child would have to go through.
These events and the depression would carry much weight well into Kyo's teenage years. He's spent his life being blamed for his mother's death and being reviled by most of his family. The only saving grace is that Kazuma was kind enough to adopt him into a loving household. Kazuma worked hard to show Kyo (and everyone else who thought to talk poorly about Kyo in front of him) that he loved him like a son. While it did have much effect in helping Kyo grow, that weight of being ostracised was still resting on Kyo's shoulders.
Needless to say, being locked away in a dark room until he dies didn't exactly help with his depression at all.
Kyo developed a lack of confidence and a sense of anxiety about letting anyone get close to him. He knew that if anyone saw his true form, they'd never accept him. The anxiety would only get worse once he grew closer to Tohru; if she saw it, he believed she would reject him and his happy days with her would be over. He doesn't truly begin to heal from all of his hurt until after he sees that Tohru actually does accept him fully, without hesitation.
I believe Kyo really grows through the latter half of the series, coming to a wonderful place when he is able to confront his father about being locked away. It took a lot of strength and courage on Kyo's behalf to tell his father that he was going to continue living as best he could. Even better is when he uses this courage to confront Tohru and tell her that he has the same feelings for her and that he wants to spend the rest of his life with her. At the time he's freed from his curse, he also seems to be freed from his depression. It's a beautifully symbolic moment.