Currently, I think Civ 5 encourages you to settle only in high production areas. If not, you end with a city with little production and this highly hurts you when trying to build national wonders.
For example, in a recent game, I soon discovered a 2 tile island with a luxury I hadn't. My dilemma was: should I settle a new city on the island or not?. The city has several sea resources nearby, so that it would reach its full potential after I researched navigation (thanks to seaports). I choosed not to settle the city to be able to build the national wonders in a rasonable time.
My proposed tweak: modify the number of cities with a certain building needed to build a national wonder. For example, require only 3/4 of your cities to have the prerequisite building. This way, if you have 4 cities you only need to construct the building in 3 of them. If you have 3 cities or less, you need to construct the building in all of them.
For example, in a recent game, I soon discovered a 2 tile island with a luxury I hadn't. My dilemma was: should I settle a new city on the island or not?. The city has several sea resources nearby, so that it would reach its full potential after I researched navigation (thanks to seaports). I choosed not to settle the city to be able to build the national wonders in a rasonable time.
My proposed tweak: modify the number of cities with a certain building needed to build a national wonder. For example, require only 3/4 of your cities to have the prerequisite building. This way, if you have 4 cities you only need to construct the building in 3 of them. If you have 3 cities or less, you need to construct the building in all of them.