Overall it looks solid, but I'd change the motherboard - I'd go for something Z97 based, since there's no reason to not be on the latest controller - M.2 support and the like are nice bonuses too. I'd recommend the MSI Gaming 5. Also I'd switch from the caviar blue HDD to a 2tb Hitachi K7200 - like $20 more, but 2x the size, and isn't a power efficient (read: slower than normal) model.
As far as knocking down the price, dropping from a 980 to a 970 would drop a good chunk of change off and still have excellent performance. The 970 is excellent value for money. If you wanted to go even cheaper, R9 290s are a bit less powerful than the 970, but can be had for around $260, which saves some more money. If you don't intend to overclock, you could save $20 by getting the i5 4690 instead of the 4690k (also could consider going to an H97 mobo in this case, but you might lose CFX/SLI support in doing so). Another $30 could be saved by ditching the aftermarket cpu cooler, which is nice, but not strictly necessary, especially at stock clocks. Finally, there are cheaper cases - Antec 300 is solid for about $50, and the NZXT source is Dang compelling for $30. That said, I won't tell you to *not* get a Define R4, since it's an excellent case, and excellent cases never hurt.
