I think that Carter will have a very, very solid career. I don't see any glaring weaknesses. I think his floor is higher than Bagley's, but his ceiling is not as high as Bagley's. Bagley's D lowers his "floor". I could see him getting exposed on D and a coach having to sit him some down the stretch... I think Bagley's defense must show great improvement in contesting shots. (he can come over from the weakside and block a shot very well, but is not good at contesting his man's shot)
Bagley has two weaknesses he needs to tidy up, defense and shooting (FT% and consistency and range on his perimeter shot). He has a high motor, so I think his defense can be much improved. In Basketball and especially the NBA, it is not only can you score... It is can you stop your guy more often than he can stop you...