I know many people like polished brass but I believe that what you want is clean brass not polished.
David Tubb in his video "High Power Rifle Reloading" states that he only cleans his brass every 3-4 times because he feels that a "grippy case" works better. Of course that's just his opinion.
Also don't forget that whatever you put on you cases to polish them is likely to end up in your rifle/pistol action. Additionally adding polish to your cleaning media may result in what I call the "mop & glow" effect. That's where dirt gets sealed into the polish and builds up over time.
Experience is a very bad teacher because it first gives you the test and then teaches you the lesson.