Hi Guys! This is my first post in a while. Just had a small doubt. What if I Have a Big FPS Game and i Scale down the size of all the objects extremely small. Would it increase my game performance and frame rate?
Thanks 
No, the size of the objects is irrelevant, it comes down to a lot of things, but the easiest way to break it up is Textures, Models, Particles and Post Processing.
The size of the texture matters as well as how complicated a mesh is (how many vertices it has), how many particles are being tossed around and how many post processing effects you use (like Anti-aliasing).