First things first. LEDs are awesome. The more you have, the better your life is. FACT.
Good. Nvidia all the way, although G-sync is nice to have it's not essential. I run at 144hz, and I'm really not sure I can tell the difference. 30 to 60hz is the real eye opener, that's when you know you are PC gaming. AMD are every bit as good as Intel these days, and to be honest better at some things worse at others, but not in a massively noticeable way.
I've been toying with the idea of running my PS4 through a capture card. You could effectively play windowed. Save the outlay for 2 screens, and you can make awesome vids too, and overlay webcam to twitch. You could be a famous streamer!
2K is dream build, and honestly you won't pay anywhere near that.