This has to be bizarro thread or something! Just kidding, welcome to the other side R-I-L. You are now far more optimistic than me, and close to everyone on the board.
Anyways, to the question:
Surprising: In order to call someone 'surprising', I need to have unreasonably high or low expectations of them. Thus, I am hoping this will be Larkin, as if he posts a .360+ OBP our offense will be that much better.
Disappointing: Again, same criteria. My vote goes to Aaron Boone. I just don't like his ML growth curve thus far. He regressed last year and still hasn't shown great plate discipline and strikes out way too much. If he is going to hit at the top of the order, he needs to stop striking out, get on base more, hit the ball to the right side to advance runners, etc. As in, he needs to make several adjustments and I don't know if they are forthcoming.