I do understand what you mean. I agree with you there, actually. Atmos for headphones lacks enough virtual room size that it doesn't portray virtual surround well enough. On the opposite end, DTS-X has too much reverb and makes things come across a bit too artificial sounding. What you need is a good middle ground. Might I suggest Creative SBX (though you'll need an extrenal device like the Creative G6). And on PC, I suggest Redscape Audio.
Both of these have granular settings that let you adjust ther room size, and both actually have a really great balance between sound quality preservation and psychoacoustics.
This is why I said it wasn't really aimed at you. I was venting in general because I do get a lot of people just writing them off for the reasons mentioned. Your post brought up some bad memories. Lol.
As for preserving as much of a headphone's signature, this is the problem with virtual surround. They just aren't unless you keep room size to an absolute minimum. The bigger the scope, the less of the headphone that remains. You have to sacrifice directionality and depth for headphone's inherent traits. You can't really have both. All you can get is what a good headphone can do to that virtual speaker room, but it's still no longer your headphone. Now it's just a great sounding bridge to that virtual speaker room, that may or may not sound better than other headphone-turned-bridges to those virtual speaker rooms.
The technology is utterly transformative.