Why did Bruce Arena take the job with the New York Red Bulls? Because he believes in dynasties, he says. The specter of the New York Cosmos looms large over Major League Soccer’s New York franchise, and many feel the lack of a strong team in the country’s biggest soccer market is one of the main reasons MLS has failed to take off. So Arena wants to build a dynasty, kind of like the one he built with D.C. United 10 years ago. Changes for next year are already under way. Among them are sweeping changes to the current roster, provided the league gives him the salary cap room. “This is a very difficult league to make changes. It’s kind of built on status quo,” Arena said after the Red Bulls’ season-ending tie with D.C. United on Sunday. “We’re hopeful that we get a few favorable decisions on our part so we can improve the roster.” After Arena brought D.C. to the top in ’96, ’97, and (almost) ’98, MLS went about dismantling the club. The league doesn’t like dynasties, which is a mentality that’s at odds with the way club soccer works in every other league around the world. Arena thinks a powerful dynasty would create more interest in MLS, not less. “Parity doesn’t bring fans to games. Fans want to see good teams,” he said. “It’s a flavorless product at times, but we do need to have years where there’s the New York Yankees and whoever’s at the bottom in baseball. That’s natural.” The real question is whether MLS commissioner Don Garber and other executives at MLS agree.