I don't see why the Summer games can't be permanently held in Greece and the winter games permanently somewhere. Build world-class facilities which will last for years with minor maintenance and easy upgradability for tech advancements. Whichever bidding nation wins the hosting bid for the year, they will provide the decoration, entertainment, and culture experience of their nation for the world to see. This way, some of the smaller nations are able to be seen where otherwise they wouldn't have been able to host by building facilities. All nations that are part of the Olympic Alliance would contribute monetarily for yearly upkeep of the facilities.