A safety rating left up to the discretion of players is bound to be abused. Polyphony instead should program a monitor into the online aspect. This monitor would grade you based on how safe you are and assign you accordingly.
what about to ban player who's an idiot driving or to bumping other off the track then have to ban him for a week as warned. 2nd is 30 days banned. like this. it will be nice to treat them to learn how to clean run with the rest of us in the race,