I don't think there are too many guys who hang around because they are too nice to leave . . . especially ones with the description you give him. You probably aren't giving yourself enough credit.

On the other side, you are probably giving him too much. What are his major flaws? If you can't think of any, then you just don't know him that good yet. He's got flaws. He's dated other women who have noticed his flaws. That's why he's available at the moment. So enjoy the attention. He's with you because he needs someone, just like you need someone.