Keys revelation in batch's semantics

Currently, we have the following semantics/classification when revealing a public key (list = batch, we assume fees and gas are sufficient) for a non revealed implicit account:

1. [ valid_pk ] -> applied
2. [ wrong_pk ] -> refused
3. [ valid_pk; valid_pk ] -> branch_refused
4. [ valid_pk; wrong_pk ] -> branch_refused
5. [ wrong_pk; valid_pk ] -> refused
6. [ valid_pk; ... ; valid_pk; wrong_pk ] -> branch_refused

• Should the cases 4 and 6 be refused ?
• What about 2 ?
• Does it make sens that a batch contains at most one reveal at the head of the list ?