I’m guessing that the game type is just down to presets so there is no actual difference. If I wan to switch between a top-down and third-person type then I don’t need to create a different type ?
Dont know what you exactly mean, but in one project you can switch between different camera/player/control types 
e.g when you want to switch from tps to fps you just have to change the position of the camera in your player bp
When starting a new game, it’s mode either 3rd person / top-down etc. Choosing one loads a bunch of presets, but doesn’t actually stricken it. In other words can be changed at any time.
Yep, you can always change it or even combine it
e.g