What is this rig going to be for? You're way overspending if it's for gaming. (which I'm presuming it is, because of the 680.)
Because they don't make use of hyperthreading, an i5-3570k has the EXACT same performance as that i7 when gaming, for $100 less.
Personally, I'd get a Gigabyte z77x-ud3h over that board. Asus is the cream of the crop for their expensive boards, but they get creamed when it comes to budget options.
Don't buy a 680. It's only 5% better than a 670, for $100 more. [Zotac is also a not amazing brand, so a good 670, overclocked, could beat what that could overclock to performance wise.] Unless you're playing on 3 monitors, the 2GB version is more than enough - it doesn't help framerates ANY, it just stores frames as they get rendered.
Get a 1TB drive (unless that drive is dirt cheap), and buy yourself an SSD. Get a 128 or 256 GB SSD, to put your OS and applications and most used games on. It's the single most effective upgrade you can do to make windows feel more responsive. (And being in-game less than 30 seconds after hitting the power button is pretty fun.)
If you like that case, go with it. Personally, I'd get a mid tower. It'll have plenty of room to fit everything, and won't be as much of a pain if portability or size becomes an issue.
Don't get a coolermaster PSU - they don't make good ones. Go with Corsair, Seasonic, Antek, XFX, ect. (If you want to add a second graphics card later, keep the 750w. If you don't, then you only need about 550w.)
Unless you're doing sound editing, you probably don't need a sound card. If you do want one, you need a higher quality one to get much of an improvement over onboard audio.