Kemp might have been a reach because it isn't certain how much actual time he will get to play with Bigbie, who had a very good spring, and Brady Clark, utility OF just acquired from Brewers, ahead of him.
I like Upton especially if he plays 2B everyday with Cantu in the minors... he could be special.
The only real "holes" or weaknesses on your roster is your 3rd OF slot, pending the play of Kearns, and 3B. I'm not really high on Tracy and I don't expect him to have a good year.
If Schmidt can get his ST woes out of the way and pitch well, and if Sanchez can deal for the Marlins, then your pitching staff will be very solid. Your RPs look good though Izzy's hip is a concern. Hip injury aside you have some good relievers in Linebrink, Gonzalez, and Tankersley who should get some oppurtunities to pickup some saves for you also and help out your ratios.
Who's available in FA? I personally think you should let go of Kemp for another OF.
Thanks for the help!