Just reading Infinity Gauntlet, and hulk had a good level of intelligence. Back then he was one of Marvel's most popular characters, and I quite liked Peter David's take. People here are refering to dumb 80s Hulk, but in secret wars he started with Banner's intelligence, although he was losing it. The problem with a fully dumb hulk is that he struggles to carry a book as lead. Planet Hulk worked because he was a little smarter.
It also works to make Hulk reasonable smart, but get stupid as he gets angrier and stronger. Then you can still use the beserker, but not as the only facet.