A slightly different approach to Dunn
Pretend that Adam Dunn is a free agent this year. Assume that he has no predispotion to play for a given team, be it Reds, Astros, or otherwise. It's all about the benjamins.
1.) What deal would you offer?
2.) What is the best deal you think he'd get (and from whom)?
Games are won on run differential -- scoring more than your opponent. Runs are runs, scored or prevented they all count the same. Worry about scoring more and allowing fewer, not which positions contribute to which side of the equation or how "consistent" you are at your current level of performance.