I think that your build looks solid. Personally I would go for an i5 4670k, simply because the cpu doesn't matter as much with games these days. Also an i5 4670k won't bottleneck a gtx 780 so you could save yourself some money there.
Mobo: I think the gigabyte board is pretty good, however if you plan to sli later you will find it hard to fit a wireless card or something else in the PCI slot under the second PCIe, as the 2nd graphics card will block it. I would probably jump for an Asus z87- pro or an As Rock extreme 4.
HDD: I would probably settle for an WD black series drive or even a seagate barracuda. If you are using it as a storage drive, those will be able to access files faster.