I have set my tce directory to be a directory on the native filesystem. Is that what you mean by a persistent tce?
I don't have a persistent home or opt. My settings tend to settle down after a while and not change much, so I just manually run 'filetool.sh backup' whenever I make a change.
I also have a 'document' directory under my home directory; it's a softlink to a directory out on the native filesystem, so I guess that's persistent.