Hi, well, the camera angle and FOV doesn't effect the flying characteristics, so it's more a matter of taste really.
If you are a beginner it might actually make sense to use a low camera angle, between 0 to 25 degrees. When starting out you are probably mostly flying slowly, then it might be best to have a low camera angle to get the hang of the controls. When you start to fly fast, you will notice that the quad is pointing down a lot. So you will probably want to raise the camera angle so you're not looking down into the ground all the time.