I have the HE1000 Stealth, ($1,399, this is not the same as the $1,999 HE1000 SE) it's very good for both soundstage and the bass depth. HD800S has the soundstage but doesn't have the bass, HE1000 has both. It's also very well tuned, the LCD-X is not. LCD-X is marginally better for bass but HE1000 not far off it, and LCD-X EQ is mandatory as the stock FR is junk. HE1000 you can stick a moderate bass shelf on, and I do, but it's perfectly listenable and has great bass extension stock. The rest of the FR I don't EQ on it.Right now I am rather leaning towards the HE1000SE because of its imaging capabilities along with the wide soundstage and detail retrieval abilities and then boost the subbass.
Only thing holding me back is that some people claim the atrium has even more soundstage depth when driven of a good fitting tube amp. It isn’t quite as good in imaging and detail though.
I might get the he1000se first and then maybe find a way to try the atrium.
If you wanted to try something cheaper just to see if you like the idea, all the Hifiman oval headphones are tuned very similarly, it's a slight step up in refinement maybe with the HE1000, at best. The Edition XS ($379) and Ananda Stealth ($399) have almost as good bass and as good soundstage. Might be an option to pick up to see if you like the idea. If you hate either of those I don't think you'd like the HE1000.
Crossfeed mixes the channels together which reduces soundstage, it's good for very artificial hard panned early Beatles or jazz but I don't get why people suggest it for wider soundstage, it doesn't do that. It can make the soundstage sound more natural though, particularly on bad recordings.