I think Davids is a fine character! Granted, he's an average kind of guy, but that't what makes him so interesting. He's just an insurance adjuster who happens to also be a werewolf. He has no hang ups or issues, like Jenkes or Ivy. He does'nt play games with people like Kistin. He's certainly not an ego-maniac like half the other characters in the books. He's just a typical guy without much baggage, and his attack on big Al shows that, like most men, he can summon courage when it's truly needed.
When you stop and think about it, David would prove to be a pleasent person to actually meet, and most of the other characters would drive you up the wall in a few minutes.