Re: What role....
Well, if that's the way you're looking at it, why even become a sculptor at all? If quick, easy to use materials are the only things you have the patience and stamina for, and if stone is such hard work to carve (debatable. Have you tried soap stone or alabaster?), then you might consider becoming a painter, instead, or at least pursuing the more "up-to-date" variety of "sculpture" being produced by the conceptualists. Heck, Jeff Koons hardly broke a sweat, let alone a fingernail, when he made his series of vacuum cleaners. No need to worry about cuts and bruises if you're just stacking ready made objects on a gallery floor, either. Look, sculpture is a lot more labor intensive than painting and yes, some of its media and processes can even be dangerous to work with, but that hasn't daunted those who are serious about sculpture. If you're looking for a hobby that is easy to do, may I suggest stamp collecting?