Not bad, but I have some suggestions:
Let me assume you will be gaming, and you have a budget.
1. A minor issue, Samsung 850 evo performs similar to the 850 pro.
The main difference is that the evo will last 15 years, the pro has better endurance and will last 20.
It is a moot point since both will be obsolete by then.
I use a 950 pro, and while it is a bit faster, I do not think it is worth the extra.
I would suggest using a 850 evo 1tb. That will hold a very large number of games. Defer on the hard drive.
If you ever run out of space or need to hold backups or video files, only then buy a hard drive.
2. For gaming, you will rarely ever use more than 2-3 threads. A I5-6600k with an overclock will perform equally well as a 6700K for $100 less.
3. If you want 16gb, buy a 2 x 8gb kit. skylake is still dual channel even with 4 sticks. Moreover, a 4 stick kit will cost more than a 2 stick kit of equal specs because it is harder to match 4 sticks than 2.
I like the lpx, no need for fast speeds which need extra voltage. 1.2v ddr4 2400 speed is about right. You gain little with faster.
http://www.silentpcreview.com/article1478-page1.html
5. the graphics card is a more difficult question.
If your games are slower types like strategy games, a single GTX1080 will be good.
I have little problem a 4k running civ 4/5 with a slower GTX980ti.
You could plan for future sli. 750w should do it so long as the GTX1080 is not a heavily overclocked version that needs more than 8 pin power.
As another option, your budget will permit a $1200 titan x pascal for fast action games.
If you ever wanted to sli that beast, go with a 850w psu up front.
In general, gameplay seems to be better with a single gpu.
In the future, I think there will be even stronger single cards available, so you could just sell whatever you buy today in favor of the next
best thing.
6. For your monitor, look for something larger in the 30-40" size. It will be more immersive and text at 4k resolution is not very readable on a small monitor.
7. 14nm skylake runs cool. No need for exotic cooling. A Noctua NH-U14s is as good as it gets. I have no problem with a NH-U12s cooling a I5-66600K@4.8 The new s variants are offset to clear wide graphics cards and tall ram heat spreaders.