Retarding the ex timing after mods ie. turbo, hi-flowing exhaust etc can give noticeable gains in all the categories mentioned by you. Advancing ex timing will make less power, torque, response etc. but also make the motor less prone to detonation. If your car is stock it's not worth touching full stop, if your car is modified an adjustable cam gear and tune is a far better idea than DIY CAS adjustment and hope for the best.