Zim can hit for a higher average than Burrell and with less Ks. Zim can hit for more RBIs too.
I don't know about the RBI. If Burrell was in the 3 or 4 spot on that team, he'd have a lot more RBI. Zimmerman will strike out more if he gets more aggressive in the future, which I kind of hope he does. The average you might be right about.