During the offseason, this is the main thing I'm going to concentrate on. I've noticed the same thing you have. I've seen that most minor leaguers end up with the same amount of homeruns every season, and it's my goal to change that by adjusting the power ratings, home run %, etc. We'll see how it goes.
I'm trying out a new method of rating guys, and Baker comes out to 40/30 {contact/power) against lefties, and 58/50 against RHP. I'm still going to do a lot of testing on this, but I think I'm headed in the right direction.