I use the favorites a lot too and it has not been working for a while. This is not the first time and one time it took a really long time to come back up.
I don't always have time to go through all I follow when I am just dashing in. I quickly check wallet and then the favorites and then if I am not in a hurry I go to my general follows.
I'd definitely like to have my favs back.
I totally agree with you. I don't think people realize just how useful it is!