That highly depends on the area, in my opinion. US East Coast alone, look how many large aerodromes are within a 200 nm radius from, let’s say KIAD. Of course, the traffic has to be split upon all these dromes since other players on other airports also want to have some traffic in the air around them.
If I’m not wrong, a radius of 200 nm equals around 125k square (n)miles so 50 aircraft is very, very low.