Welcome from San Diego!
I just bought a 2015 Street 750 about 3 weeks ago. First mod was a bar end mirror on the clutch side and extended mirrors on top. Also added the tall boy seat, back cargo rack, sissy bar, screaming eagle slip on and screaming eagle air intake. Just got the stage 1 upgrade today. What a difference! Way more zip off the line.
Also, pulled off the front plastic thing over the headlamp and removed the rubber from the forks. I think it looks better. Finally, bent the rear brake pedal up and re-welded it. It doesn't sit flat anymore and works great.