Everything looks great Would just change one thing - the power supply. The 850w G2 from EVGA is a superb power supply, and will be perfect for upgrading to SLI in the future. The 650w just wouldn't cut it in the long run.
Your cpu upgrade options are as good as it gets. Either broadwell or 4790K.
But... I really doubt that you will ever need such an upgrade.
More likely, an upgrade will be in the graphics card area.
To get significantly more graphics, either through a single stronger card or sli GTX770, you will need a better/stronger psu. 850w for sli, perhaps 750 for a titan Z.
Corsair CS is only middling quality. I suggest a Seasonic or XFX unit instead. 750w for a single card, 850w for sli.
I would go with a 240gb ssd up front. 120gb can fill up quickly. SSD prices are reasonable now.
Perhaps even defer on the hard drive if you don't need the storage space immediately.
8gb is all you need for gaming. You are good there.
But, if you ever anticipate 16gb, I suggest you buy a 16gb kit up front.
While adding a second kit will probably work, no ram vendor will support different kits.