Big fan of all the proposals in here and huge thanks to @samehueasyou for writing it up so well.
As part of this, I have put forward a specific RFC to tokenize the vault shares which will allow them as collateral in borrow/lend protocols. That RFC can be seen here → [RFC] Transfer Vault Rewards from staking to Merkl and enable tokenisation of Vault Shares
As part of this RFC, it will require Vault Rewards to be migrated to something like MERKL.