I think your pick of hardware is pretty solid. Personally I´d skip the LED lighting.
The motherboard you picked (Asus MAXIMUS VIII HERO) features SupremeFX ROG and is a OEM-branded version of Realtek chipset. More than often, you´ll get a rebadged software, that makes it look like a premium offering, but its still a Realtek or other cheap chipset on a riser card.
The sound isn´t great and will probably sound a bit flat, poor bass and perhaps some EMI noise.
Personally I think dedicated soundcards are vastly underrated. And I believe the reason, is that alot of people don´t realize that they also need good speakers/headphones to hear the difference and a basic understand how to connect speakers correctly and the settings in the software. With a dedicated soundcard (even cheaper ones), you can experience clearer, crisper and fuller sounds. Sometimes new sounds that won´t be played with onboard audio.
To me, the sound is at least 15% of my playing experience, and that makes it important enough for me to spend a little extra on the quality too.
As a sidebonus, your gaming rig will free up some resources, as better soundcards have their own rams and audio processor.
The soundcard I am using is Xonar Essence STX from Asus, and it supports Direct3D and Creative Labs EAX realtime surround effect. It gives good surround sound experience, and you can track other players locations more precisely and hear distances more clearly. After my old soundcard was damaged, and I got used to hissy pc audio, I am really happy to have a good soundcard in play again.
Note – decent speakers/headphones are a must. Much like, if you use premium cooking gear, you may get a premium meal, provided the chef can cook and he uses quality ingredients.