Forget the rating floor idea. The ratings on here are pretty messed up compared to actually chess ratings. The ratings should be calculated based on the ratings the players started the game with!!!!
So if you were a 2000 player and you started a game, and during the game you resigned a whole bunch of games and your rating dropped to 900, and then you lost the game the calculation should be done using the 2000 rating and not the 900 rating so the opponent gets the points he deserves. Thats hows its done in OTB and it should be implemented over here too.