Speaker Imaging - Do you hear a line, or do you hear an arc??

Before room treatment-
     Definitely an arc.
     Center image not settled in the center.
     Little or no depth of soundstage.
     Images seemed to be easily perceived from left speaker, area 
     between the speakers, and right speaker, ie- the speakers did not 
     "disappear".
After room treatment-
     Front line well established.
     Sides of soundstage extending beyond the edges of the speakers.
     Nice depth of stage extending beyond front wall (the wall behind
     the speakers).
     Center images well-established, solid and 3-dimensional.
     Soundstage is now taller, wider, and deeper and appears more
     of a box instead of an arc.
     Front of stage either appears in front of speakers, in line with
     speakers, or behind speakers, depending on recording.
     All images seem more 3D, more round, less flat.
     Speakers disappear convincingly.
Room treatment on all four walls plus ceiling.
Dedicated listening room.
Dedicated AC line to room.
All gear plugged directly into wall.
Speakers are Vandersteen 2Ce Sig IIs.
No rack between speakers.
No TV in room.
Dire Straits and Pink Floyd always sound very well recorded, as do most classical and jazz.
Most rock and pop sound surprisingly good now that the room and setup were established for best sound to "play the room".

Tom

     

Erik-
Thank you for the kind words.
Sorry to hear about your lack of a listening room. Especially a shame since you were the first person here to mention any kind of room treatment to me several years ago. You said try hanging some blankets on the walls. Well, I did just that and was amazed at the difference it made. Thus began my quest of focusing on the room more than the gear. My system is very modest but sounds wonderful to me because of the room treatment and meticulous attention to the setup. 
And thanks again for helping me get better sound than I've ever had before (going way back to the 70s).

Tom

@ieales- thank you!
@erik_squires - hope you finish it soon, and do reward yourself!

Tom