It's all well and good to nitpick and find reasons why traditional pitching stats aren't good enough, but there's a very famous quote that goes:
"Fine, Jerry, if we're not going to use ERA anymore, then what the hell exactly are we going to use?" (Abraham Lincoln)
I'm glad our 20th (or possibly ninth) President of the United States has asked this question, because it provides a perfect lead-in for this post. There are, in fact, two very useful advanced metrics that not only do a great job of measuring true pitcher value, but are also nearly guaranteed to make sure you never get invited to a party again.