As a former wrestler, it is my observation that most fights end up on the ground--which is obviously where I'm most proficient. So I opine that wrestlers make the best fighters.
On a purely anedotal note, my father, who was an All-New York City offensive lineman in high school, told me that when he used to go out with his friends who were football lineman and hockey players, they all agreed that the people you didn't mess with were the wrestlers. No matter how much bigger you were than them, they'd get you.