As stated many times I'm not a college fanatic so my exposure is limited.
But based on the videos I've seen of Maye and Williams I think I prefer Maye.
I get that Williams has that kind of Mahomes vibe for people with the improvisational talent, but that's a hard thing to bank your franchise on, and for the NFL I'm really looking hard at what kind of starting toolkit the QB has particularly above the shoulders.
(I really liked Richardson as a prospect last year despite a similar profile but AR still seems like a potential freak of nature type QB if he heals fully, so we'll see.)
With Maye, from what I've observed, nothing rattles him. He's consistent and measured in the pocket, and the level of preparation and practice and pure QB drilling he's done his entire life is obvious to me. Same footwork every time, same arm mechanics (unless he needs to throw a crazy off-hand TD while scrambling....nuts), same steady and calm movement of his head through his progressions while set to throw, etc. I haven't looked it up but I'd bet he was either a coach's son or was involved in a LOT of QB specific practice early on in life through HS and college. *
Williams OTOH plays like me and my buddies when we'd bloody each other in pickup games in the back yard or some field full of rocks and glass. I know he's not out there drawing up plays in the dirt but that SEEMS like his background.
Plus you can't argue with size as a starting point, imo. Maye is 6'4" and plays like it. Williams is only 6ft and has like 5lbs more weight (granted probably muscle).
Both have elite arm strength and can make passes all over the field, but my sense is Maye is going by the book and picking apart the defense while Williams mostly finds a way to fit the ball into space. That concerns me because NFL DBs will bait QBs like that and have greater closing speed than college DBs.
tl'dr Maye looks like a polished can't-miss NFL ready QB and Williams looks like a high risk/reward lottery ticket. Given the history of this franchise I think you need to take the safer option.
*edit: there it is....from an article "Maye's father, Mark, was a quarterback for the Tar Heels in the 1980s, and brother Luke sparked a national championship run for UNC basketball in 2017."