I'm disappointed that WPA was left off of everyone's list.
wOBA is great and has more predictive value, but if you want to know who had the most situational value, WPA is the way to go. It won't tell you much about how someone will do in the future, but it does give a better picture of who was producing in high leverage situations.
I like to use it in tandem with wOBA because WPA is a counting stat and wOBA is not. That way, you can kind of knock down some of the noise of wOBA in small sample sizes.