Steel flex is not a lot of work. I was a nervous wreck after reading the "Everything Steelflex" thread but its not bad at all. That being said, fixing the rivots is the best solution and then Steelflex for protection. Fill the boat with water, mark the leaky rivots and then get to rebucking. Its quite simple to do and dosnt take a lot of time.
To answer your question though, no, paint is not going to fix your leaks.