Bill Hoover,
I must amend my response: I am neurotic. It would drive me crazy not knowing what the new room may yield in terms of performance gains. If you tend not to be so crazily compelled, note...
Your current perf resulted in a scintillatingly positive review, particularly noting the mind-blowing imaging. Since the primary Gladys question is imaging compromise, it would probably be easier to at least initially temporarily remove her and note the effect.
Mentally scanning the proposed transferral experiment: not only will equipment movement be involved, but you will really have to exhaust all speaker position possibilities
(assuming 155" wall only) and definitely preferably some room treatments before a determination can be made. At ~250 lbs a Summit side, the work total work and time required may significantly exceed that which is necessary to temporarily excise Gladys.
155" = 13'. This vs 20'. Very significant distance to sidewall difference. 6' vs 2.5, assuming 8' separation. You will almost certainly have to room treat to absorb that first sidewall reflection. Even if successfully effected, this may not yield the expansive soundstage to which you are accustom.
Room volume: 2930 vs 2160, app. Substantial difference.
I doubt you'll achieve the bass energy development and overall scale of performance in the small vs the large, current room.
If the Summits had trouble driving big room, there would be no question about moving, but we know that certainly is not the case.
In summation:
1) If it's driving you nutz, move.
2) If it's driving you quasi-nutz -- Gladys removal experiment.
3) None of the above -- leave it alone.
It is possible Gladys has a positive effect on what sounds like superb extant bass performance.
(Open to correction on all of this guys).
Dave