I like
Yasir,
Farhan, and
Ilyas for a different character in my story, who is more happy go lucky.
I agree that the meaning of
Hasan suits the character, so I'll certainly consider it. It is interesting that the historical
Hasan was poisoned by one of his wives. She probably hated living in a harem. According to the internet,
Hasan spent his time "making and unmaking marriages" and there are some pretty wild estimates on how many wives and concubines he had when all his divorces are added up. If this character was a womanizer, I would definitely use
Hasan.