Maybe with ease of aim on FPS certain guns need more recoil or less power from console to PC. But for general gameplay balance issues I don't see what would change in a port.
Aim sensitivity is the biggest factor. Manually controlled turrets, for example, could not have a forced low sensitivity on PC like it could on consoles. I don't know if MNC has any manual turrets but the principle remains the same. The ability to aim much more quickly and accurately means weapons need to be rebalanced. Movement would ideally be faster too, since it looked pretty damn slow on X360.