Here's a basic litmus test to determine if a stat is a "good" stat or a "bad" stat...
Does that stat rely highly on the 1 vs. 1, pitcher vs. batter phenomenon that makes baseball so conducive to statistical analysis? Then it is a good stat. Examples - OBP, K, BABIP, etc.
Does a stat rely highly on the performance or influence of players or people outside the P vs. Batter battle? Then it is a bad stat. Examples: Pitcher W-L record, Saves, RBI