Well, if you are going to rotate I assume you aren't looking for something super expensive (Some Like it Hot is one of my favorites in this format). And I tend to avoid inserts that have been minty-whited... although I do LOVE the idea of a Jaws/Jaq combo!
I think 1984 is when they stopped making inserts, but that still leaves some fun titles that can be had for a reasonable price... Once Upon a Time in America, Streets of Fire, Ghostbusters, Swamp Thing, Conan, First Blood, American Werewolf in London, Scanners, The Thing, Escape from New York, Prom Night (great use of the vertical format), The Shining, Blues Brothers, etc... And of course there are a bunch of Moore Bonds that aren't too expensive.