The Salmon colored Kool Stop pads have always been a popular choice for pad upgrades. Ask a local shop and see what those guys recommend. If your rims are old and worn, take the time to wash them down with and scrub them with a scouring pad.
If you mean a "Brake Booster", it really depends on your setup. I've found boosters to be more effective on steel frame, and less effective on aluminum, due to the differences in tubing diameter and stiffness. On the front end, the can make all the difference in the world on a flexy fork.
Boosters work two ways, one by preventing your stays from "bowing" when brakes are applied, the other by preventing them from "winding up" torsionally. In either instance, it's forcing the energy you input at the brake lever to be imparted to the rim, and not towards flexing your frame's tubing.
Again, stiffer, oversized tubing has a higher resistance to this type of flex, so your mileage may vary.
If you do decide to try a booster, I highly recommend the DKG Gorilla.