He's dated several women over the years, and never has anything bad to say about them - not even his ex-wife. For example, he once mentioned Padma Lakshmi in an interview and spoke very highly of her, saying "Padma's not afraid of attention. I've been out with a lot of women, who are very, very pretty, very, very beautiful — but I would say to everybody that in terms of intelligence, Padma Lakshmi was off the charts. She is so bright."
His fans also get their moments (both heartwarming and awesome). Someone recently posted a video of themselves harassing Keaton when he was out on a jog, and calling him a motherfucker. Cue outraged commenters saying that the poster was a despicable human being and should be ashamed of themselves.
Same goes for the comments on most of the news articles (tabloid and otherwise) posted about him. There are very few negative comments.
An example of this would be in the Daily Mail, an English paper that's borderline tabloid. They recently posted a few articles saying how Keaton was getting old (he's 62), his hairline was receding, he wasn't in the best shape, etc. 99% of the comments on the articles were calling out the Daily Mail and praising Keaton.
He regularly promotes his son's work on his Twitter feed, and you can tell how strong of a bond they have - he proudly shared the fact that his son had helped write Demi Lovato's song "Heart Attack", and is known to have used some of the money he made from his films in order to help his son succeed in his own endeavors.
Really, his relationship with his son defines CMOH. They're always supportive of each other, they regularly post photos of themselves (and other family members/friends) playing baseball, having supper together, and generally being normal, happy, and healthy. In a world where you're constantly reading things about other celebrity families imploding, it's refreshing to see.