I pretty much agree with what Danny said. You have a solid foundation to work from, you just need to work on picking up on any openings that your opponent gives you, and exploiting them in your work. I'd suggest reading the works of others, see what they do, and try to develop your own style around it.

If you want to work in trash talking in specific, the Federweight title is a great place to start.

As a general rule, you want your RPS to be relevant to the match, entertaining, and sell yourself over the other guy. Tell us what makes you so special, point out anything that could be considered a weakness with your opponent, and make me want to read from start to finish.

Most importantly though, write what makes you happy. If you are enjoying what you write, then others will as well.

Like I said, you're starting off with a good foundation already, just some small tips to help you improve.