The question here is, lead is the best because of it ballistic qualities and cheap price, whereas all the other alternatives are either expensive or have little or no ballistic qualities.
We don't know what the future of lead will be however what we do know is, that the best alternative to lead ballistic qualities, or tungsten, isn't going to get cheaper. There are just way too many applications for tungsten and its properties in today's world.
"The free element is remarkable for its robustness, especially the fact that it has the highest melting point of all the elements. Its high density is 19.3 times that of water, comparable to that of uranium and gold, and much higher (about 1.7 times) than that of lead."
"Tungsten's many alloys have numerous applications, including incandescent light bulb filaments, X-ray tubes (as both the filament and target), electrodes in TIG welding, superalloys, and radiation shielding. Tungsten's hardness and high density give it military applications in penetrating projectiles. Tungsten compounds are also often used as industrial catalysts."
