I don’t think it is, aiming for 7° with the ability to go at least 1° in either direction seems about right to me. With power steering the additional steering effort wouldn’t be an issue, that’s really the only reason I dialed mine back. Although I do think you’d want to look into how much jacking effect you’re getting once you get into the +8° range since that does have the potential to upset the car’s balance on turn in and transitions if it gets too extreme.