If we ever do something like this again where it's clearly partisan (We could do it with the senate perhaps) we should divide up into two camps, Dems and Reps. Each side ranks five Presidents they want to keep off the island. After each five rounds, the lowest ranked President would be put on the island to be voted on. This way, people like FDR or Reagan wouldn't be voted off until at least Round 20 or so, but they aren't protected the whole time.
or, alternatively, anyone who chooses to restart these Presidential Threads from the very beginning (i.e. Round 1) could list only those presidents from the late 18th and 19th centuries (from George Washington to William McKinley) for the rest of us to choose to eliminate.
they must not under any circumstances list any 20th or early 21 century presidents (from Theodore Roosevelt to George W. Bush)
until those presidents from the preceding centuries had already been dealt with.
