Aren't there already two season fives and one season six on the archive site?
There is this:
Beyond the Fourth Season Unfortunately many of the links are broken. The stories are around but you have to "fight" to find them.
It would be nice to have an archive-based group with links that all work.
When I first got interested in LC Fanfic, I collected all of these I could find. I have three different versions of Season 5 (S5, TUFS and one that I don't remember where I found) and one version of season 6 (S6).
Bob