This is just for gaming? Redirect some money towards graphics cards. I haven't tallied the cost of all this stuff you've listed, but as it stands, one could build a system that performs twice as fast as yours in games for significantly less money. And by saying that, I'm not saying that you're spending too much money (that's completely up to you); I'm just saying that you might feel silly having a super expensive system that costs a grand or so more than one that does its job twice as fast.
But if money is no issue, just add another 7970 to your current list and call it a day. Or maybe you go for 2 680's. That's assuming you're usage is for games and not much else. Maybe you need 7970's for compute performance?