Actually to be honest, I prefer the dentist drill to the new one. While its really annoying, I have begun to associate it to a sort of high tech thing, and a change into an obnoxious jackhammer would lower the tech.
It's not currently a jackhammer sound. Still sounds like a drill, just lower pitch to cut out some of the annoying high frequencies and a few alternate hits so you're not hearing the exact same sound every time. They will be implemented in 1.0, then I'm open to suggestions.
EDIT: Oh, and on a side note, a jackhammer wouldn't fit into my design philosophy. They are pneumatically powered, whereas electrical tools are almost exclusively powered by motors and servos. The sound will fit my concept of how the tool actually functions. I may go as far as drawing up rough schematics on how the machines and tools operate.