Had a 2007 bagger that I kept stock. Hated riding it. No power, crappy seat, terrible sound system and really bad suspension. Needless to say, I didn't ride it much. When I traded in 2012 it only had 5000 miles on it.
Bought a 2012 FLHXSE3. Without even test riding it, I added: Drago's 2 into 1, TMan Cam, TTS Mastertuner, Tuned by a pro, Corbin Seat and some minor cosmetics. This, I was pretty happy with.
Six months later, I kept reading on this forum the guys doing a little more engine work to be really happy. So, time for a little engine work: Sent the Heads to TMan to grind, port and polish, Bottom end to Dark Horse to true, weld and balance, SE 10.5 pistons, Lifters, Throttle Body, Rods, New TMan Cam, Tuned by Robin 125 squared. Extremely happy camper.
More forum reading, time for new bars, new sound system and new suspension.
More forum reading will make you spend money, but you'll probably have a bike that you'll keep forever.
Seriously, you don't need to do all that I did to be very happy with your bike. I would always recommend: Exhaust, Cam and Tuner. That alone will make you very happy with your bike. After the 2007, I would never even consider leaving one stock.
Cowboy