I know it was a bit of a tack on at the end there, but there are a lot of other possible set ups the Olympics could introduce to lower costs for cities, while also keeping it interesting.
The one I like most is switching the games to a home city every second time, it reduces the pressure on cities every four years, and that decrease in supply of event slots could increase the value to cities of hosting the Olympics every eight years. As ongoing venues obviously Athens, Greece would make sense for the Summer Olympics, and maybe Stockholm, Sweden or Chamonix, France could become the Winter Olympics home city. (Just basing that on a quick search of the games history)