You, sir, are awesome. I've shot my own companions numerous times out of sheer frustration, so they'll probably appreciate your efforts as well.
As for turning the voice volume down, I'd like to speak to others. It's the insanely repetitive speech and noises driving me nuts.
Keep an eye out in the mods forum here for a mod I'll release within the next few days. The sneak comments (at least) will be changed to happen once a lifetime, and a few other things will work better. It'll be named FoNVPhalanx.