Right now, the Featured Game trophy only counts currently featured games. It seems to me like there should be some way to "count" games that used to be featured.
(This next part is tsmpaul's suggestion [hope you don't mind, paul])
"Maybe they should have a 'Previously Featured' icon that can appear next to games' names, if they had once been a featured game, but were removed so newer games could go up? That way games are still marked as having been exceptional games, giving the author recognition, but it allows newer games and authors to get recognition as well?"