Did Maeglin had a chance?

Maeglin had the same chance to be good that all the other characters in Middle-earth had. The element of free choice has been mentioned. That his father was hard on him is neither here nor there...many people (both in fiction and in real life) have hard, even cruel parents. What determines the outcome is exactly "free choice" ... how we choose to respond to the circumstances we find ourselves in. And our choices do not exist in a vacuum. Choices have consequences, for the good or for the bad.
What "doomed" Maeglin was not so much his circumstances, but his attitude. Maeglin wanted what Maeglin wanted, without any regard for anyone else. It is his complete self-centeredness, IMHO, that dooms him.