The lens is more imporant than the camera body. It would be pointless to have 50MP if the lens can't resolve the detail you want.
When you get into the 1D & 5D series bodies, you probably want to be looking at Canon L series lenses. There are some 3rd party lenses that are also very good. Usually (but not always) the Canon L series lenses are the top performers.
And since these are expensive lenses... this is an area where you might want to rent your potential lenses before deciding which to buy. This way you can make sure they'll be suitable for your needs.
The quality of your images will never exceed the quality of your lenses. If you use consumer lenses, then your photos will look like they were taken with a Point & Shoot.