No, WAR is not the only stat, but it's better than WHIP. The main problem with the Tigers pitchers is that they can't stay healthy and any stat that doesn't include innings pitched is not going to explain that.
Personalties? What makes you think that Manning, Mize and Skubal have better personalties for success than Fulmer and Boyd? Neither one of us knows these guys personally. You know, I really hope this current group does better, but it's tough to predict which young players will succeed. i know you think every Tigers prospect is going to be the next great thing. I wish I could be that way, but I can't. 😀