My sister lives south of San Francisco, and her DD (who is likely more gifted than mine) is well-placed, neither the smartest nor the most advanced, in her age-appropriate non-magnet public school class. Feel free to PM me for the school name.

We live in the Midwest, and my DD is not well-placed even after a grade skip. So from my perspective, I would not be looking for the school with the best gifted program, or the most flexibility for skipping. I'd be looking for the school with "lots of kids like mine."