After reading about the state of the variants in the industry, it does appear that a crash could be incoming. I am no marketing guru, but if you wanted to create a secondary market for collectors, why not go the print run method. X first print, first run books with a specific cover. X second print, first run books with another cover. Hell, you could even number the print run books if you felt the need to. Once you are done with the variant runs, start the second prints, unnumbered. People can still get all the second run covers at a reasonable price and all the collectors can fight for the numbered versions.
I dont know, just a though.