A minecraft world,instead of being infinitely flat,be a finite cube planet!

Minecraft worlds are unnecessary huge, causing that, an average player surely won´t travel more than thousands of blocks from spawn; by the other side, community survival worlds, may travel more, but the point is, millions of blocks will remain unexplored, the solution that I suggest is that, instead of being infinite, make it finite, the size being customizable and creating the illusion that we are playing in a planet.

How would it work? , well, I´m not a programmer but I know It´s doable; the world would be just like a cube, divided into faces that, at crossing the invisible border, the game will now load chunks that are from the face that the player is heading to, and, going at the same axis, will, after going throughout 3 faces, will end up at the beginning; the size of the world would be based on the size of a face, for example, I´ve calculated and, if we make a cube world with the size of an actual Minecraft world, a face will be 16000kmx16000km big. For a cubic planet be playable will need at least, have enough size to have in, all biomes and Minecraft structures; and finally, a cool detail would be that going up, you will be able to see a face of the cubic planet 

The advantages that this would´ve are that players could explore the whole world, map it, and have a good idea of its size. This could open up the chance for players to recreate and create planets, with custom biomes, custom planets acting more like dimensions; and also the chance of a space update.