Bidding war aren't done to double spend others transactions but to prioritize one's transaction block inclusion.
You said "improve zero conf further" my claim is that RBF does not decrease btc zero conf security but indirectly increases it and that bigger block increase zero conf security to the same extent that a transaction with above average fee on btc is more secure than a lower fee one.
You realize that similar bidding war should occur on BCH with barely more transactions (10x)?
Quicker mini block? Like reducing block time?
RE: What I think makes Bitcoin Bitcoin, and why I think Bitcoin Cash is Bitcoin