My experience of deleting my Facebook account back in 2009 (and reading this the process hasn't changed) is once I finally deleted it, it was stolen by someone else within a few weeks (I'm guessing automated / bots trying to steal identities). I have a very unique name which, as far as I'm aware, is the only one in the world. What caused me to notice was friends still on Facebook who were getting this fake profile recommended as a possible connection.

Facebook ignored requests I made (submitted without having an account) that the profile was fake. I also had friends report the account for me but it still exists today - this is the fake account https://m.facebook.com/harry.fuecks - thats not my picture.

So beware - it may be more pragmatic just to deactivate your account than delete. That means Facebook gets to keep your data but at least you don't risk identify theft.

Ultimately think it's going to take regulation to solve this problem in general - it's not in Facebooks interest to make account deletion painless.