The idea is not bad. I'd say its pretty good. But i think what it needs is more content. For example, I can make a lot of puzzle games and Build up money and fame. It also starts to get boring after some minutes.
I'd say that you should add more genres or themes (by themes I mean "Zombie" or stuff like that)
I'd also say that the games you make stop selling after sometime , since I can just make 1 game and wait until I become rich.