Seems a good idea to me. It's madness for a country in a new area to invest silly money on white elephant stadia in an attempt to out-trump their neighbours. So yes, share it around.
Odd caveat only allowing cities with two airports to host a match, one per country on the other hand is fair.
Only Wembley will fit for England. Glasgow is out, so is Cardiff. Munich too.....
Should mean great demand for tickets, no need for stupid infrastructure projects and a final set piece in a chosen venue. It sounds as though Turkey will get it, fair enough. Just better hope Greece don't get to the final....