Okay I have a kind of weird question/request. I know absolutely nothing about higher quality music or headsets.

I'd like to find some headphones, mic is optional, that would be good for gaming and listening to music all around.
The weird part is that I'd really like to find some that are also customizable.

The Crossfade M-100 is probably the closest I've come to finding exactly what I'd like. (I love that customization options and that you can get things engraved on the ear plates.)

However, having basically no knowledge on headsets, etc, I can't decide whether or not these would be a good purchase.

Budget - I can spend up to 300 USD. Can be flexible though.
Country - United States
Source - Computer and iPhone 5s.
Requirements for Isolation - Noise cancelling is always good, but I'd put a higher priority on no leakage.
Preferred Type of Headphone - Full sized please!
Preferred tonal balance - I'm not sure, I've never had high quality headphones.
Past headphones - I currently use these for gaming and Senn' CX215s for mobile.. Once again, due to lack of experience I can't rightly say.
Preferred Music - I mostly listen to 'smooth' EDM. What is called liquidcore in some circles. But my top YT playlists are... This, Studio Killers, Mylo Xyloto, and Gorillaz. Nightcore is also a guilty pleasure.
What would you like to improve on from your set-up - Just an all around upgrade I guess, lack of experience keeps me from knowing what I want for sure.