1) A great graphics card
2) Great CPU
3) An ASUS Z170-A will do you just fine. The Pro and Deluxe have WIFI built in. If you need the WIFI, go for the Z170-A Pro
4) 2X8GB is fine. If your paying a lot more for 3000mhz ram, don't do it because 2400 or less is fine
Thanks,
Reese