Re: save failed due to insufficient space...
This is a fairly rare issue on PC....Play Station users on the other hand have this for many different games.....and thus while it is a bug or issue, it is most likely something specific on your PC causing the issue. Either a game file got messed up, something in the registry, something with the hard drive, another program interfering with the saving, or a setting in your system is causing the issue.
Now comes the hard part, figuring out which of these is the issue and correcting it. You made a good start with those changes, but you you will also need to continue checking until you find the issue. A DxDiag file posted here may give a clue for us to help you, also disabling your Anti-virus while you play and seeing if it makes a difference would be good things to do for further help.
As far as EA "fixing" the game, not going to happen, because all patching stopped just after the last DLC was released and that was years ago, not to mention like I said at first, this is a fairly rare bug on PC that usually has less to do with the game programing and more to do with specific computers.
So please continue posting here and maybe we can help you figure something out....start with the DxDiag file...