Could have been great
A great idea, good acting, funny script, poignant characters. But sadly, all over the place.
They really dropped the ball on the pacing of his redemption. His personality is a douche who starts to get better, then reverts back to a douche. He starts getting better again, then reverts back to a douche. He starts getting better yet again, and again for no discernible reason he reverts back to a douche.
It should have been a gradual redemption, otherwise why would we care whether he wins, loses or draws? The whole point of 'feel good' redemption movies is for the viewer to immerse themselves in the character and empathize with him. That way, they care about him and then feel good when he comes around.
When it goes douche - good - douche - good - douche - good etc. it doesn't matter how the movie ends because you don't really believe it's the end. Even though the last thing is good, you are still going to suspect him to go douche again.