Regarding Brake Force, you should set it at a value that feels natural to you. Your starting point could be something you are used to from driving your own car in real life. Real racing cars tend to have a very hard brake pedal with little movement, so adjust the pedal resistance as well to your liking. Then let the value stay for at least 2 weeks and do a lot of practice. Get used to the weight and feel of the brake and let your muscles and brain learn to drive with the Brake Force value and resistance you chose, it's called muscle memory. Then you can start tweaking, but when you change it, you should try it for 2 weeks of training before you get settled in and choose if you want to stay or go back to the original value.