My 2c:

Full RBF is the only option that makes sense.

The RBF behaviour is not part of Bitcoin, it's just a node implementation detail.
Anything prior to consensus is not sacred. As long as a block follows consensus rules, it is valid, regardless of what transactions it includes from the mempool.

This is a key difference between Bitcoin and the shitcoins.
Bitcoin doesn't try to get fancy implementing all kind of "social consensus" rules and other such stupid non-deterministic things.

Users expect determinism and reliability out of the Bitcoin network. There should be no features which rely on the goodwill of node operators.
This is akin to building an extension to your stone fortress out of paddlepop sticks.

The same goes for any feature which attempts to treat the mempool as sacred.
The mempool is a resource to be plundered in the greediest way possible. It is a Herbalife salesperson's phonebook.
Any implementation details which try to get nodes to treat transactions in the mempool a particular fashion is foolish.

Miners ought to order transactions by fee revenue and nothing else, otherwise they are in the wrong industry.
If there are 50 pending blocks, and I submit a transaction with a higher sats/vb than the rest, rational miners should include my transaction first even though my transaction is the newest.