There are two main categories that go into designing a video game. First you need a detailed, but exciting and remember able gaming level. Then secondly you need well crafted and an easy on the eyes protagonists. Most designers spend a huge chunk of time creating the perfect character that everyone can relate to, or will at least admire. Someone that's likable or even lovable.
Instead of spending needless amounts of time doing such a thing, there are games that try to implement you as the protagonist, sometimes you are given the freedom of creating your own creator. Here are some examples of games that gave you this freedom.
First, here is World of Warcraft, where a huge chunk of the world is effected by:
Or a more detailed game is Elder Scrolls Oblivion:
The reason that this is a brilliant design decision is because it gives free reign over the story, we are not following the actions of a single person and how they feel about the situation they are in, this puts us the user into the game, like how Mass Effect gives you choice not only in look, but in opinions and choices in making game changing decisions, what you say or do, or how you act towards people can seriously effect the overall design of your character and his world.
Character creation is a genius idea because of how deep the system goes. Most games let you govern over a basic skill set, but games like Mass Effect and Oblivion let you completely restructure your characters face. You determine the shape, width, height shade, or length of every attribute on the body.
Even though character creation is very important to the overall design of the game, nothing is as important as the layout, the level selection, or the overview of the game.
This is a map of Zelda, A Link to the Past:
Now if you look closely you can tell where thee game is divided into sections, this game's level design is so highly regarded, some deem is the pinnacle of video game design. It is a completely open world game, meaning every inch of this map is explorable to some extent, and there is something to do anywhere you go. If you look at the overview you can see how they implemented lines and shading, everything from the forest to the mountain top is distinguishable, and playable. This is just the tip of surface for video game design.
Another highly regarded level design is the one found in Castlevania:
The best part of the Castlevania design is that it takes the basic concepts found in the original Mario or Donkey Kong games where the levels are designed to be linear, or just trying to get from A to B without dying. But Castlevania adds the twist of letting you explore regions that don't necessarily pertain to the story. You can explore any number of rooms in the castle, and you can go back and forth as you please. Back in the old days old days of gaming you would have Mario climbing a ladder to save the princess from a giant monkey. While this showed a good use of lines, from a design stand point it was too linear. Now days designers need to focus on making the game complex, people want unique experiences.
Today designers have a lot more work cut out for them. The old system doesn't work any more, people don't like to play the same game with a different skin. They want new environments, they want new hero's. Designing a video game level or protagonist involves many hours of work and effort. While it is a very difficult job, i believe it is one of the most rewarding when the finished product brings countless hours of joy to various people.