For me in Coco (it's been a while so I can't really remember it) he only part I didn't like was the ending when both dead and alive members of the family were celebrating and dancing. Felt a bit cheesy or something to me.
For me the sad part is when the guy in the flash back is playing "remember me" to his daughter.
"A human destiny, but nothing human inside.....
What will be left of me when I`m dead?... There was nothing when I lived..."