Applying to colleges is not a double blind science experiment. The kid is only going to enroll at one college, no matter what application strategy you follow. So you’ll never ever see the data from the road not taken.
So long as the schools on the app list are pretty good fits, any of those schools will work fine. So don’t overthink it. If there’s really not a clearer favorite, I’d go for the ED favorite and be done with it.
When the kid comes home for frosh year Thanksgiving break, odds are that the kid will love school #1 and will say they can’t imagine going anywhere else. And if the kid ends up enrolling at school #2 #3 or #4, the kid will say the same thing.
My kid and her HS friends all love their schools today. Most wound up at school #2 #3 #4. Most kids kids bloom where planted. Most kids love the one they’re with.
“2) ED at one of the reachier schools within her top four, on the grounds that that is where she would arguably most benefit from the ED boost relative to the RD round (her GPA and standardized test scores are in 25-75 range for this school, but standardized test score is not at the top of the range),”
Be careful about this. ED usually doesn’t turn a 25% stat RD reject into an ED admit. More likely is that applying ED gets a 60% stat kid in over another similar 60% stat kid who applies later in RD.