Facebook is supposed to be a social networking site. It should help you meet new people. Instead, now Facebook is just a record of the network of people you've already met.
A standalone chat application. Many people don't care about the content of their news feeds, but everyone is on facebook, so they use it for the chat. A stand alone chat application would allow you to be social on a desktop or laptop while having other pages or programs open and not having to resort to using a second device.
File Transfer Many of you may remember the good ol' days of AIM. Everybody was on it, it was the social networking tool of the 90's and early 2000's. AIM used to have a lovely option called Direct File Transfer. You could sends gigs of data, pictures wouldn't be compressed, you could send music and movies, pdfs, installers, anything!
Your old social networking tool used to have file transfer integrated, the social networking tool you're using today does not. People have to resort to third party websites and software, large files are slow and tedious, and the largest files can't even be sent without some premium service.
I already hate facebook too much but um can't totally ignore it cause i can't get all of my friends to switch from social networks to good ol days, now can I ?