I just recently purchased a RS as well. I have been adding a few mods/maintenance. Started by changing out the O2 sensor which was a big improvement in my case. I have installed the Brake! brake light module which is pretty trick. Just got and will be installing a headlight modulator, turn signal cancellation relay (has lots of other functions as well.), and louder horns. I also found that a couple of seals on the shifter linkage were pretty dessicated so I changed those out. The rubber sleeve on the shifter was pretty loose and was missing some bushings. Changed out the footpeg rubber pads and I changed out the handlebar grips as they were a bit worn. Will be performing a little maintenance along the way on doing some of the installations. When I was installing the handlebar grips I found out that the throttle cable was out of adjustment. Adjusting the cable was another notable plus.
Later next week I will be taking it to an independent mechanic who will give the bike a good going over. Will address issues with a leaking crankcase breather tube and check to see that work that was done at a dealer was actually taken care of, (the bike had a 12K service, new tires, new brakes, one month before I purchased it.) After that the Wilbers shocks should be in and will be installed, as the stock ones are probably shot.
Other than that I am not anticipating anything else. I am more interested in initially making sure that the bike is up to snuff with all maintenance and is in overall good condtion - at least verified by a professional.
Pretty much after all of that I still need a good tail bag/luggage rack, the PIAA lights would be nice with the switch module that uses the turn signal cancellation button, stainless steel brake lines are intriguing, maybe the Hyperpro steering damper (if the stock one is bad) and the Rhinewest Cam & Chip kits is somewhat appealing, though I wonder what kind of long term effect it would have on the engine and reliability. I am not interested in an aftermarket exhaust as I like how quiet the stock system is. i Have not ridden the bike on long enough of a ride to come to some conclusion about the seat (a common mod) though it will have to be replaced at some point in time. If the stock seat is relatively comfortable I would probably just replace it, otherwise the Sargent seats look nice - don't care for the looks of the Corbins. Other than small little items/accessories that would be about it.