Factual error: When Leon gets shot in the head, Deckard is untouched by any blood, brains etc despite being directly in front of him - he should be covered in something from the head wound.
Suggested correction: From a human, yes. Leon isn't a human. We don't know anything about replicant anatomy. For all we know, they might not have any blood, and their brains might not even be in their skulls.