One rule can be added to Instant Runoff Voting to make it much less likely to eliminate the most popular candidate.
1. The quickest way to win any IRV election is to win a true majority, meaning over 50% of all first-choice votes. This rule could be expanded, to check for any Condorcet winner (undefeated in head-to-head matches). Presto, IRV now complies with the Condorcet criterion.
2. One bonus weird trick: Use IRV to eliminate all but the top five candidates, then apply Condorcet method to determine the winner. If Condorcet gets stuck, use IRV to eliminate one of the tied candidates, then go back to Condorcet. This would provide even better insurance against IRV going goofy, because even more most-preferred candidates would be protected from elimination. While this is not 100% Condorcet-compliant, the miniscule chance of eliminating a Condorcet winner in 6th place is probably not worth worrying about.
Please add either suggestion to your IRV proposal.
Basic outline of my practical ranking election method: https://americarepair.home.blog/2020/12/13/brief-summary-of-practical-condorcet-election/