If you start having problems chambering or extracting fired cases, it will likely be due to a build up of powder residue, and perhaps plastic from the cases. A good cleaning is the answer to that. And since you are having no problems, cleaning is all that is needed.
Polishing a chamber is something you do when there is a problem, and one that cleaning won't solve.
Polish the wrong way (or with the wrong materials) and you can change the chamber dimensions, possibly enough to ruin the barrel. It's tough to do it polishing by hand (but you can do it) and incredibly easy to go too far with a Dremel or other power tool. Unless you know what you are doing (and have had practice) and have a need to polish the chamber, I would recommend against it.