Sorry about “next season will be the last,” but I think we’re lucky to get another season at all. The ratings have never been stellar. It’s a show for a select audience, though we can hope that audience will widen at least a bit.
Noah Hawley claims that the show was planned to have a three season arc from the start, though. Which if true seems preferable to just keeping things going with no real plan as to how to resolve them, as has happened on other shows…
It’s shown that his real dad is a powerful psychic (chalkboard scene) and in a wheelchair (Amy’s memories). I can’t remember at the moment if we also see if he’s bald. That’s a bit more than “very, very lightly”, particularly in the context of the Marvel universe.
He is bald, but in a “simplistic line drawing” sort of way, nothing that screams “Charles Xavier” for someone who didn’t already know about it or that breaks plausible deniability if they didn’t have the legal right to mention the character.