I have no issues at all when it comes to adding friends on Facebook. However, I exceeded my allotted friend count a very long time ago. All Facebook users should know by now that ordinary profile-pages are only allowed 5000.
So, before sending friend requests and friend suggestions, please look at my profile-page first (From my understanding, Facebook is supposed to notify people that I have exceeded the specified limit of 5000). Although I am filled to capacity, anyone is free to subscribe to my Facebook updates.
In the future, Facebook might consider increasing the so-called friend limit to a larger number (Hmmm. There is a part of me which believes that Facebook will not be doing that anytime soon).