that link takes you to a kinetic energy calculator to play around with.
after checking out that calculator and plugging in my personal set up, i have to say that adding mass is the way to go, for me at least. best case scenerio is to add mass without sacrificing speed. however, if you just add mass to your arrows and do not change your bow, you will lose speed, thus decreasing your potential final kinetic energy. however, i plugged in values for my set up and compensated for loss of speed, and came up with better kinetic energy by just adding mass to my arrows. adding mass decreased my velocity, because i did not figure to change my bow. however, adding mass added kinetic energy, even though i lost some velocity.
on the other hand, the only way i have to gain speed is to lose mass in my arrows. losing mass requires a significantly large amount of speed gained to make up the kinetic energy. if i used an arrow that only wieghs 7 grains per inch, which is very very light, i would pick up speed, and so my kinetic energy could increase. but i would have to pick up a lot of speed. i would need to pick up about 30 fps just to break even on kinetic energy. if i wanted to gain kinetic energy, i would need to see more than a 30 fps increase in speed. would i get that? i dont really know, i would have to get a chrono graph and test it. however, just based on estimation, for my set up, i would conclude that adding mass is the best way to go. if you can add mass and add velocity at the same time, that is ideal. or if you can just add velocity some how without giving up mass, i would do that as well. with a fast shooting bow, the best compromise is probably right around that 9.5 to 10.5 grains per inch of arrow, or maybe even a little heavier. however, I shoot maximas, which are light by hunting arrow standards, and get 75 foot pounds of kinetic energy with my set up. thats good for deer.