Despite being relatively new to Marvel Comics, Miles is an incredibly important character who deserves to star in an awesome animated movie.
As a well-established writer and creator in animation he lends a certain amount of clout to the movie.
His first feature film work as a writer is on Legendary’s forthcoming live-action Detective Pikachu, making Spider-Man another big project on his resume.
On the other hand, Hirsch has a lot more television experience than he does in the realm of feature film.