i'm satisfied with my stock exhaust system. the cans are big/thick and fit the styling of the bike. I concede they should weigh less.
because sport bike riding is somewhat physically challanging, and when riding aggressive, you need to 'fit' properly. making your bike fit you ergonomically as much as possible is important. this will not only increase comfort but also distance and even safety. Positioning the bars and improving the position of the pegs are two relatively inexpensive mods that make a huge difference. There are several options for both as i'm sure you are already aware.
congrats on your bike, familiarize yourself with it and have some good old fashion two-wheeled fun.