I would step down from a Core i7 to a Core i5, due to the fact that the Core i7 is for editors an there is no difference between either in gaming applications. I would go for the Core i5-4670K. Pretty much the darling of the PC gaming market. Overclocks like a madman and uses a low amount of power at the same time.
I think that 16GB is maybe something too much for a gaming rig. If you really intend to use it for heavy video editing and more of those things...yeah, get 16GB but you're saying that it is just some light video editing. I believe that 8GB will do for playing games. Same as dottorrent: i7 is not really necessary in your case.