Peter David spent years making the Hulk either Gray or "Merged" and was much more intelligent. The Gray Hulk was a selfish jerk constantly spoiling for a fight, while the Merged Hulk wanted to use his strength and intelligence to do some real good.
An element of the Savage Green Hulk that works is that he has a "fighting savvy" worthy of a professional fighter. The "Brainless" Hulk is surprisingly on the ball when it comes to combat.