The original planet of the saiyans was planet sadala(it got destroyed so they took over another planet and called it planet vegeta)

Iirc planet plant is only mentioned in the episode of bardock which is not canon

Yea sentry is not that known and personally i dont think his race is a part of his character sonit doesn’t really matter

Not a good casting imo

He can defo play a good sentry no doubt hes an good actor he just doesn’t look the part he gotta gain lot of muscle tho good thing the movie is delayed