We just need a lottery system for popular places. An amount reserved for locals, the rest for foreigners. Each year, if you didnt win, you get increased chances for next year.

Having people paying 5 or 20€ more wont make any difference. And increasing that amount will only make it impossible for normal people to visit these places.

If Santorini had 1/10 the visitors it has now, it would have been truly magical, like it was in the past.