The manufacturer will label the shaft's flex point based on how the shaft affects trajectory. And once again the correct shaft flex is more important than kick point in achieving the correct ball flight. The golfer should be able to tell you if they like a heavier shaft or a lighter shaft. If they have no preference for a specific weight, then refer back to their swing speed and the ball flight they are trying to achieve. Graphite shaft designers can make a lightweight shaft with a higher flex point but this would be considered an exceptional design.
Lighter shafts do help generate more club head speed for longer drives.
The torque value of a lighter shaft tends to be high because of the weight. A higher torque value means a shaft will twist more during the swing. Most of the time, better players prefer heavier shafts because they are not concerned about club head speed. They are looking for more control. It is easy to make a heavier shaft with lower torque values.