Everywhere I turn lately, I seem to be running into this nonsense about "zeroing out the settings" in ACR and LR.
It's completely silly. All you achieve by setting everything to zero is to make your photos look utterly awful. (The benefit, I suppose, is that when you've finished your editing, it looks as though you've made AMAZING improvements.)
Defaults are just defaults. They're a starting point. The truth is, no matter where the sliders are when you start, you still have to move them on a photo-by-photo basis, to get the best results every time.
If, for example, you go to the trouble of changing the default setting for the Brightness slider from 50 (Adobe's default) down to 0, then habitually find yourself moving that slider up to about the 40-60 range every time, then you've wasted your time, haven't you? Wasted it in changing the default in the first place, and wasted it making those big adjustments on each photo.
The truth is, Adobe aren't silly. They've given us pretty darn good defaults. But if you're not happy with them, set your own. Maybe your camera's images look better with the Contrast slider at 10, not 25. Maybe you're a habitual overexposer, so your Exposure slider should start at -0.20. Etc, etc.
But don't zero.