So to be honest I have dropped this drama at ep13, not because it was bad but because personally, it made me quite depressed thinking about life and I may pick it up again another time.
My mister is one of those dramas you either love or hate, and even if you hate it it's not because it's not good but because it doesn't fit your genre style well. If your a hopeless romantic or into high action this may bore you. But if you love deep meanings or genres that reflect everyday life with character depth then it would be a perfect fit.
I love that the ML isn't this perfect guy who has life all figured out but he is a normal working man with a crazy family, struggles and hardships and he makes mistakes but is so good compared to those around him. The FL takes no crap and fights for herself but also allows herself to open up to him. There's no romance and if there was it would have ruined it.
Just people finding friendships and learning that life sucks but it's a little easier with others around you.

I am not gonna say much more about the rest of it. I wouldn't re-watch because It's one of those dramas you carry in your memories.