I think every QB in this class needs a redshirt year, honestly. All of the top guys have flaws that could be exposed if thrown into the fire. Ultimately, one or two will play early and it'll be up to them to adjust. Watson has the big game experience, Mahomes has that don't give a !@#$ attitude, I think they'd be the best candidates to play in Year 1.
With Cardale, I never really saw anything that tied in to his inaccurate throws (why I refer to him as "fundamentally inaccurate"). With Kizer, it's 95% down to lazy feet. The kid might never solve the issue but that's the beauty of being this distanced from the situation, hard to find out about a work ethic.