I hear you. You want to see new and original ideas. Ones with unexplored worlds or maybe something different in the gameplay. I remember playing games like Braid for the first time and being impressed by its innovation and design. Or even Call Of Duty 4 and Resident Evil 4, both revolutionary at the time. But video games are expensive to make. Very expensive. And when you are talking about big titles companies are spending a lot of time and money to bring the game to the store. Because of this they want to know that they are going to see a profit for their investment. This is why you will see franchises that are known to sell come out a lot more than new IPs.
Games take at least two years to make. Some more. That means you are paying for a team (a large one according to the credits) for years before the company sees a dime. A the technology and the electricity bills. It is a risky endeavor and one you want to pay off. It is also easier and quicker to make a sequel to a game with the same engine as you can reuse it.
This leaves a couple of options. You have kickstarter and indie games to mix things up. Braid being an example of a great one. But it is hard for a small team to match the quality for a big studio and indie games do not have that shine as big titles. But still, wit their own style, they can be masterpieces. Big companies can also take chances on new IPs in between their big launches. If they make their money from their call of dutys and their assassin creeds it can give them some room to risk on a new title.
I am not hating on any title that has a lot of sequels and it is cool that played who like the game get more of it, but new titles can be a great experience that a lot of players want.
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