As an IU grad, I am riding high these days and have Mendosa mania!
Has the size (6'5"), footwork, accuracy (75%), ability to fire through tight windows, touch, play-action passing, ability to throw on the run, decent mobility, high IQ, high character, and arm strength to go top 3 for sure.
There was a comment about relatively few deep balls, and that's true, likely because IU has a O line of road grader run blockers who are less adept at pass protection, so they get it out fast. That might be the team's main weakness, facing teams with awesome pass rushes., though Oregon qualifies, and they handled it (at Oregon, no less). He shows the arm strength on quick outs to the strong side sideline, a throw most college QBs won't try, and especially in play action he has shown the deep ball touch more often in recent games, with some drop-it-in-the-bucket long strikes with touch and as accurate as a handoff.