There is no such thing as "future-proof," but I believe "future-resistance" is attainable. The key is not only a specific level of performance, but sticking to very high quality, and making sure upgrades are possible.
For example, one of the Asus "Sabertooth" boards won't get you any better performance, but will provide milspec components backed by a five year warranty. Similarly, WD Black hard drives also have five year warranties. If you think you need 1TB, get 2TB; if you think a 128GB SSD boot drive is enough, get a 240GB-256GB drive for that future-resistance.
You may only run one graphics card, and power requirements are dropping, so 550W is probably enough; BUT adding a second card down the road for Crossfire, SLI, and/or GPGPU coprocessing (e.g. PhysX) justifies getting 650W, or even 750W. I'd choose an 80+ Gold Seasonic PSU, which also have at least five years of warranty coverage.
Consider the games you play, and the settings you find acceptable. Some people insist on "UltraMaxOhWOW" when really, "very high" or even "high" settings look pretty darn good. Look at the benchmarks, and budget allowing, buy a graphics card that is a few tiers on the monthly chart better than you need now; it will last for years (much as my HD7870 has been lasting me; the HD7970 I bought for mining is getting insignificant use now that ASICs have made GPU mining obsolete).
Between "targeted overkill" and buying quality, you should be able to build a rig that will last for years.
Facebook
Twitter
Instagram