It depends who you put on the mic, have Miz or Punk on the mic regularly and they'll run with it as seen already. A streak can get anyone over as evident with Goldberg who wasn't good in the ring and mediocre at best on the mic but simply got over because he won...alot, sprinkle in his physique and appearance and you have yourself a "legend" whether you like it or not.
Depends who the wrestler is. If you have a guy like Goldberg or Andre the Giant, obviously a winning streak would be better for them because they aren't that great on the mic. If you have someone like The Rock or Steve Austin, mic time would pay off more.