They are not stupid questions at all.

A good way to tell if a bigger carburetor will increase performance it to connect a vacuum guage to the intake manifold and put the engine under full load (wide open throttle in a high gear right through the rev range). If the guage doesnt drop nearly all the way to zero and stay there as the revs increase, there is a restriction in the carb or air cleaner. If this is the case a larger carb will help performance.

An engine and it ancilleries are fairly well matched/balanced from the factory to do their job. If you change just the carb you may get a performance increase but not as much as if you change all the other components on the engine to match/balance with the new carb.

Hope that makes sense