Would center channel benefit audio only room?

Tvad, at a normal range; the volume does not alter the soundstage one way or the other.

Lars, Zu Essence has also discovered, "Less is more". They call a 2 way 1.5 which is what it is. To add without adding.

Take my word for this. The problem I have is the result of some unique room acoustics that can not be altered, consequently I will have to discover and emphasize the affected frequencies. A problem of this nature will not change with new speakers.