If you want a custom gaming rig, then build it.
Except for the cheap cases, off-the-wall PSU, and so-so motherboards, you have a good parts list.
Buy a solic case with good airflow. Looks are important, but function is more so.
Don't skimp on the PSU. Go with a solid name (Antec, SeaSonic, Fortron) and more wattage than you actually need (call it overhead).
The new NVIDIA 680 boards are starting to come out, and they leave all the Intel boards in the dust.
Oh, and don't go wireless if you plan to game. Take the money and buy a longer CAT-6 cable.
My Rig: SABLE
Antec 300 Illusion / Antec EarthWatts EA650 650W / EVGA GTX 760 2GB
AMD FX 8320 x8 Black Edition / Gelid Tranquillo / MSI 970A-G43
Sandisk Ultra Plus 128GB / Samsung 840 120GB / WD Black 750GB / WD Green 1TB / WD Red 3TB
G.SKILL Ripjaws 2x2GB DDR3 1600 - Crucial Ballistix Tracer 2x2GB DDR3 1600
Win7 Ult 64-bit - Func MS3 Mouse - CM Storm QuickFire Rapid Mech Keyboard
R.I.P. Danny L. Trotter
... 14 Nov 1945 - 4 Sept 2009