I don’t see this as the standard’s role. The contract is obligated to make sure delegation is always used with a correct leader.
In the current reference code:
we indeed verify the specific leader. Likewise you can add additional delegate entries that forward to other actors/templates in the app, but then it’s your obligation to verify that all entries of that leader are consistent with the delegation (it also becomes a custom way to transfer the token).
Adding a batch leader to the standard itself requires justification and would also complicate the std and make it a multi-contract app. If anything, I think it should only be an optional addition/extension (ie in a different KCC).
I might be missing details or usage context you already have, so I’m happy to be corrected with more info.