Summary:
Can I program a \"thick client\" game in C without reinventing wheels, or should I just bite the bullet and use some libr
I'm surprised nobody has mentioned XNA. Its a framework built around DirectX for doing managed DirectX programming while removing a lot of the fluff and verbosity of lower level DirectX programming.
Performance-wise, for most 2D and 3D game tasks, especially building something like a fighting game, this platform works very well. Its not as fast as if you were doing bare metal DirectX programming, but it gets you very close, and in a managed environment, no less.
Another cool benefit of XNA is that most of the code can be run on an Xbox 360 and can even be debugged over the network connection was the game runs on the Xbox. XNA games are now allowed to be approved by the Xbox Live team for distribution and sale on Xbox Live Arcade as well. So if you're looking to take the project to a commercial state, you might have am available means of distribution at your disposal.
Like all MS development tools, the documentation and support is first rate, and there is a large developer community with plenty of tutorials, existing projects, etc.