Anything over 130% is too high and makes the games way too long. I found that 110-115 is a very good balance. Personally I think giving 20 HP/AP would be really good. Putting players at 159/139. This allows a lot more freedom with rushing as you don't feel like you will die instantly, and decreases the amount of "luck" kills (e.g. someone randomly hitting 2 PBs on you).