There should really be an option to see all friends of yours that are currently online.
(Same for people you follow and people who follow you if you wanted to see also)
This would be pretty easily done most likely just by a little drop down button that would say something like "Online Only" on the friends page, followers page, and following.
It would help out just to see which of your friends are online so that you will be able to more easily navigate through who's online and who isn't than having to go through page to page |