Future-proof doesn't exist, it's computer hardware they release new ones every year. No one knows how long an i5 will be good for games, that depends on how much time game developers spend on coding support for extra threads into their new games. If it was me buying today, I'd get the 6700k/7700k because newer games are trending towards supporting more than 4 threads. If all you do is play counter strike/LOL/DOTA/Overwatch, then maybe the i5 is a good place to save a few dollars. For what it's worth, I'd wait for Ryzen to come out before buying anything. Even if you don't end up wanting something like the R7 1700, then the prices on the 7700k and 7600k might drop some.