Welcome! Nice bike... you got the best one in the best color!

I can help you spend TONS of money on it...
You should get the CVO Supplement for the FLHXSE3. The wiring harness on our bikes is a bit different in some areas from the regular lineup... particularly the audio. The supplement contains the wiring diagrams, and discusses all of the differences from the regular Touring bikes. You should get the Parts Catalog for it, as well.
Please post the particulars on your build when you know them. Decking the heads increased the compression, and you need to know what cams you're running, of course.
Other than that, pretty much the same as the other Touring CVOs. We do have the adjustable non-air rear shocks, which are far better than the stock air shocks. The fork innards need work... I had the Traxxion Dynamics forks put on mine, but folks in the know say the Progressives are nearly as good for far less money.
From your pic, that is not the stock seat. Did you get the stock seat with the bike? In my opinion it's pretty worthless anyway... it's quite thin with little support, and you can't put a standard backrest on it... but it looks good. FYI, the FLHXSE3 came with a passenger sissy bar with a pad that matches the stock seat, too. I point that out because some people are sticklers for getting all of the stock equipment with a used bike. I sold my stock seat and sissy bar, and got a Corbin DualTour, plus a Mustang Super Touring Wide Vintage seat for two-up riding. I don't plan on ever selling Honey Badger anyway!
The Dunlop stock tires don't seem to last very long... especially the rear, depending on how you ride. I'm on my 2nd rear, and will put new rubber front and rear for this year's riding season. The tires are pretty expensive, and the only tire options I know of for our wheels are the H-D Dunlops, unfortunately.
Ken