Put all small P/P schools in 3A and all 3A+ P/P schools in 5A. Then use the SF from there.
I don't support that, but I think it would solve most of the complaining.
Also, I've long supported the 1A/6A ~32 teams (probably less), then evenly distributing 2A-5A (5A wouldn't be a 32-team class). But take it a step further and go to only four classes -- 2A and 3A would need an extra week of tournament games.