You really ought to read the first post, it is up to date and explains a lot. I was saying "Fun" vs. "Competitive." Many things can make gaming immersive, sound and directional soun is part of a greater whole. So you're partly right. Some of it is personal preference, like in my case I think it's cool when you hear a sound that you aren't sure came from the headphone or something in your room. To others immersion = exciting sound, where things are boosted and the visual/audio special effects are impossible to ignore.
Skyrim and Fallout are about as "Immersive" as games get presently, though I would say Starcraft and Diablo are definitely competitive games (even if you're just competing with the game). What kind of headphones do you have now? Have you experienced Dolby Headphone to simulate surround sound, and does that interest you? Are you looking to buy new headphones? What is your price budget? You may be able to get more immersive sound by buying something other than a new headphone, and all the info on the first page of this thread (starting with the Astro Mixamp, though I use my receiver for Dolby Headphone) is the best place to start narrowing things down.
The Denon D7000 usually retails for about $1000 US, for your information.
I do not yet have any headphones. I own speakers and am looking to get into headphones now. I have access to incredible discounts on many popular headphones due to my job. I am planing on building a computer in the Fall/Winter. I have not experienced Dolby Headphone. Although StarCraft and Diablo are competitive, they does not require directional queues. The Elder Scrolls and Fallout series thrill me and I want to get the best balance of soundstage (directional queues) and a flat enough response that details are not left out of most any frequency. I want bass, but not so much that it dilutes any other frequencies. From the little I've read, I am led to believe that the D7000 has excellent bass depth but does not overpower. Nonetheless, I am still in the beginning stages of this process.