Thanks for reading and for the question! Nothing wrong with gaming on a Mac, a computer’s a computer. :)
I’d personally lean towards that first option. I’ve never seen a Cloud Revolver S for less than $149, so if you’ve got a source where you can get one for $120, that’s tempting!
But the first option is interesting because you’ve included the E1. The E1 is a versatile little sound card…and it also includes an amazing microphone. In fact, I think the mic inside the E1 is much better than the mic included on the Alpha.
That means you could plug just about any headphones you wanted to into it and still have a gaming setup, as long as you don’t mind clipping the E1 to your shirt or positioning it somewhere kinda close by.
Don’t get me wrong, the Cloud Alpha’s are great overall, but if you wanted to you could pick up some good studio headphones for the same price like the Pioneer DJ HRM5’s, the M40X’s, the Sony MDR-V6's…etc.
The versatility is why I’d pick option 1. You’ll get a great setup for now, and have a lot of options to expand in the future or try out other headphones, without sacrificing a microphone.
Creative claims that the E1 can drive headphones up to 600 ohms…and while I wouldn’t personally try going that far, I’ve driven 250 ohm DT770’s with it just fine.
Hope that helps you out! Thanks again for the question.