Martel or Steamboat? In Martel's case, he was the AWA world champ when the promotion took a back seat to WWF and NWA. He had a long reign (nearly 2 years) and was an excellent worker. The title still meant something.
 
Steamboat was the NWA world champ for 3 months. His matches against Ric Flair were some of the best of all-time. Like Martel, he was excellent inside the ring. I think is reign was to to take the belt of of Flair for a while to see if he could draw as champion while Martel was asked to carry his promotion and Martel took on more challengers.
 
That being said, I am going with Rick Martel.