This would be a pretty evenly matched bout with both men in their peaks. I think Gagne has the voting edge for 2 reasons...
- His influence over the rest of the industry. The AWA served as a launching pad for the careers of many future all time greats, including Hulk Hogan, Bob Backlund, The Road Warriors, Ricky Steamboat, Iron Sheik, and Ric Flair himself. Verne established himself as one of the most iconic trainers and promoters before the Vince Jr era. Even when the WWE was putting other territories out of business the AWA was able to continue on for an additional 7 years before folding due to lack of resources.
- His consistency and appeal. Ric was a staple of the NWA and later JCP/WCW in the 80's when the former became associated with it. The territory was not as hot as the WWE at the time, and unlike the AWA, JCP had the resources to keep up with WWE. And I think a lot of that had to do with Ric's lack of appeal within his territory. Some would argue the mismanage of Jim Herd, which is certainly a fair point, but Herd didn't start his tenure until the late 80's. So that's 5 years of NWA/JCP/WCW not being able to keep up with the rapid expansion of the WWE when they should have been able to. Verne Gagne was one of the most popular wrestlers in the US in the 50's. He was given a limited version of the US title based out of Chicago, but thanks to his appeal he was able to boost the credibility of the title to the point where fans not only saw him as the top US champion in the nation, but as a worthy successor to the NWA title. Many fans and promoters saw the value of having Gagne as the NWA champion, and he was passed over simply due to political influence. He later founded his own version of the AWA, the old one had roots tracing back to Tony Stecher, and by placing the newly christened championship onto himself he was able to raise the it's credibility until it was eventually seen on the same level as the NWA world tile. A lot of people here tend to give Gagne a bad time for booking himself as champion, but he held the AWA title for a combined 12 years. That's longer than Flair held a world championship. And when you hold a title of that magnitude for 12 years in a region and drew the money that Gagne did, then you're a universal success.
So consistency and appeal, and overall influence is why I am voting Verne over Flair here.