Keep in mind though that Harry was a Gryffindor and a Parselmouth
No he wasn’t. Common misconception, loads of people somehow missed the revelation in the book! Harry was NOT a Parselmouth; his body held two souls – his own and a fraction of Voldemorts. It was Voldemorts soul that could talk Parselmouth, not Harry’s. I highly doubt that after the Horcrux was exorcised Harry could still speak it. (Which sort of defeats the purpose of Dumbledore’s drosho in Book 2, but what can we do? It’s true!)