By 'Pro Wrestler', I take that to mean someone who encompasses all of the skills and traits that define someone as a true overall superstar (personality, charisma, in-ring ability, mic skills, etc.) By that criteria, Piper is definitely one of the most deserving guys to have never worn a world championship before. Hell, arguably THE most deserving, in fact. I'm not even a huge fan of the guy personally, but he was one of the most effective heels of the 80's and his rivalry with Hulk Hogan was a huge selling point of the very first Wrestlemania, so there's a lot of objectivity in saying how he could have made a great champion had they passed the title to him at a certain point back then.
While we're on the subject of 80's superstars who could have made good champions, Ted Dibiase, Jake Roberts, Rick Rude, and Mr. Perfect are names that are worth throwing out as well... Dibiase is probably the most ideal choice because it would have went well with his "Million-Dollar Man" persona, and like with the Piper example above, he was actually involved in a storyline with top babyfaces like Hogan and Savage that revolved around the WWF Championship at one point, so...
Razor Ramon would have made a great champion in the 90's, too. One of the first-ever "Anti-Hero" characters in WWE and a hell of a personality, worker, and in-ring psychologist to boot, he was also one of the most over faces of the "New Generation" era. And his character loved gold, as evidenced by the gold necklaces he wore around his neck. Seeing him win the world title and proclaim himself to have finally grabbed hold of the most prestigious and priciest gold of all (not to mention he could have had a good title reign with the likes of Bret Hart, Undertaker, Shawn Michaels, Diesel, etc. as his opponents, nearly all of whom he had history with that they could reference) would have been fitting for his character.