Welcome!
I agree with both posts above. Learn the bike, understand it, get a feel for it. From a Kawi 900 to a Rocket III is quite a jump. If you did buy it new (or barely used), break it in first. Get a season on it before. You already own one of the most distinct machines on the road, be patient, make your mods for you, not the fashionistas in the crowd.
You might like it louder, you might like it shinier, you might like it a thousand ways you don't even know.
Have said all that, change the seat first! Your ass with thank you when you do start to truly enjoy the bike on some long days!