Here is a build with a 6700K, MB, Memory, and M.2 SSD (512 GB):
I'm assuming that you'll continue to use your video card and case. The 6700K by all accounts a good all around processor for gaming and productivity. If it were me, I'd opt for the newer 6 core Intel but it requires a different motherboard and is hard to find right now. You could also save slightly by going with a non-"k" processor but your resale value will be lower as well.
I really like the Cooler Master Hyper 212 series of coolers. It's a bit tall but it's cheap and effective. Noctuna make good air coolers but they are pricey. Whatever you decide, make sure it clears your memory.
I've been running an MSI board for 7 years without issue (knocks on wood). They also have a very good support site where you can research RAM compatibility.
For the RAM, I like Corsair. I've heard G-Skill is also good. Avoid high clocked RAM because it's too expensive for no perceivable difference in performance. I didn't check the RAM included in the list below on MSI's website, you'll want to do that before purchasing.
The M.2 is optional and you would be just as happy with a standard SSD for your boot drive. However, FP put one in his build and says it's wicked fast. You could save ~$50 if you opt for a 256 GB or go ahead a spend the $200 on a SATA 1 TB SSD. The only thing I know about the M.2 is to avoid Intel's 600p. They didn't review well and don't have the warranty like Samsung's.
I didn't put in a power supply but you'll want to get something newer. I'm really out of the loop on these and couldn't tell you what to buy. Corsair and SIlverstone used to be good brands. Get a supply with a single 12V rail with at least 60 Amps.
For a video card, I like EVGA's cards and service. The new 1070TI is out if you want to go all out. However a 1060 should suffice for moderate gaming.
One note is that I wouldn't buy from Newegg anymore. Hit up Amazon or your local Microcenter.
https://pcpartpicker.com/list/KFhzqk
