The players decide how many worlds there will be, as it depends on how many territories are minted. The curve will probably be downwards as the price increases.
When you assemble all territories in one country, the territories will burn and become one deed. This makes the game deflationary. A deed might give you fewer points but in return, you’ll begin to earn daily tokens equivalent to the point value of the deed and gain access to the art collection. Get an overview here
The supply of artworks depends on how many of that particular deed are assembled. The more difficult a deed is to assemble, the more likely it's rare.
The artworks are limited and will always only consist of 237 countries, 6 continents and of course the crowning glory of the rare World Deed.
The base price is only valid for the first who claims. Afterwards the price will increase with a multifactor of 2x for each claim. This makes it beneficial to being early and keeping the supply limited.