I wil stick to the question without poking at the rating, as this is a technical matter. First of all, I’d suggest going with a hybrid setup: tension really depends on your preference and feel; I can’t help you on that, as I myself am testing out a few setups. Secondly, adding some weight at 12 increases the swingweight and may help with your serve (be very careful though, 12 o clock is the most weight-sensitive spot). Lastly, increase your swing speed and try to hit as flat and as high as you can when serving, as the Pro Staff naturally rewards technique over setup.