Welcome to the site from sunny Southern California! Where are you from?
Your initial power and sound upgrade path should be:
1) Remove the stock air intake system and place a filter right on the throttle bodies. Popular filters are (3) K&Ns, Ramair, and others.
2) Replace the entire 1-5/8" exhaust with one from CES (1-7/8", Australia), Reband (1-7/8" Australia),
@Paul Bryant (1-7/8" New Zealand), or Carpenter Racing (2" New Jersey).
3) Get the bike dyno tuned using TuneEcu (or at least put in a tune designed for a '16 Roadster with those mods using the TuneECU Lonelec cable).
Doing all three together will drop 50 lbs from the bike (heavy cats in both mufflers), eliminate the factory lean running conditions, sound awesome, and give you a smooth 155 rwhp and 155 ft-lb tq. Don't do one until you're prepared to do all three.