I found the kube v1 a little congested (not exactly narrow but a little compressed or lacking air) but that was initial impressions pre modding and burn in. It may also change after burn in but I couldnt say as I modded mine early.
The snow lotus 1.0+ CE (if you've heard that one) has a respectable fairly spacious soundstage to my ears, a little more than the sr2 with added air also as it's more open and has more refined and extended treble. But again my sr2 does not have 100+ hours burn in so maybe I have more improvements to expect?
I think imaging quality is slightly more important. Earbud soundstage is still earbud soundstage, it's never going to be 'out of head' and around the room like a speaker system. But good imaging can really make everything seem more realistic and you forget about the soundstage pretty quickly IMO.
That's why the ourart TI7, penon bs1 and my k's ling are quiet special to me. All have moderately spacious soundstages but nothing astonishing. But all three image incredibly well especially the (TI7 in the mids) so it just sounds right and engaging. Instruments and vocals seems like they have a place and are not mushed together.