I think the biggest and probably easiest change towards fixing the olympics is to move the ownership of TV rights from the IOC to the LOC (Local Organizing Committee). The LOC can pay a franchising fee to the IOC for the use of the olympic brand, and the IOC can continue to enforce standards and pick a venue and guide the whole process through, but if the money is actually coming in to the local organizer instead of getting skimmed off at the top, there's a lot less opportunity for corruption in the IOC.