TatsuyaShiiba
I hope he won't turn out to be some super speshul secret true descendant and heir of both Ravenclaw and Slytherin. I don't mind him being a lost son of some OC magical family, even if it seems they're powerful. It was somewhat interesting how you solved the problem with Parseltongue, by having the locket give it. Still not sure what you'll do with Slytherin's Heirship, would be cool if the locket - as it has special powers, and is the key to Salazar Slytherin's sanctum, so it should be the thing that makes one the Heir. Parseltongue will also be a boon in getting the Gaunt Ring, adding another "proof" MC totally is the Heir of Slytherin, honest, and you should all kneel before him you filthy purebloods. And he'd gain 1/3rd of the Deathly Hallows, arguably the most OP one - if you can use it - for calling the best minds in history to share their knowledge and maybe even secrets. And, to start gathering ammunition against Dumbledore, to protect himself. He could call people who knew him to learn Albus' secrets, all the dirty things he did, and maybe even if he was the one who killed Arianna.