I totally agree with points 1-4, especially point 1, as regards top-ranked schools. It's always worth noting that those rankings only point out generalities, and such data is not useful for predicting individual outcomes.
As for point 5, I'd say that personal experience can be VERY useful, so long as the parent doesn't make the mistake of overly identifying with their child, understands how their child is different from them, and respects them as individuals with their own identities. Our children are still very much like us, so we have some unique insights into how our children will respond to certain environments based on our own personal experiences, where those similarities come into play. These augment our insights gained from observing our children over time, and the unique insights our spouses can offer based on their own, often different set of similarities to the children.
For example, I have so much in common with my DD in the cognitive domain that I've often joked that I have the user's manual to her brain. I can follow or lead her thoughts like nobody else. So when she entered K-1, I had some unique insights into exactly how the environment was fitting her, based on my own experiences. I was able to tell the teachers a number of things they would have seen from her, informed by my own experiences, and they confirmed them. My family chose not to skip me, and that was the right choice for me, based on a number of factors/concerns. I was able to tick off all of those points and show how they didn't apply to DD, so the correct choice for her was different.
DW, on the other hand, was able to provide unique insights into how DD was reacting to the environment, because she shares some personality traits with DD, particularly in the emotional domain.
