Imaging/Soundstaging - Does room size matter?

Looking at the photo of your system setup your speaker positioning seems like it should give you pretty good imaging. It might be time to look at your gear also, though speaker placement is the number one factor in imaging I think some gear just images better than others. So it may just be that your ss integrated just doesn't do the imaging thing that well. Also keep in mind that some recordings, especialy vintage jazz, is often recorded with a hard left-right pan that keeps the sounds stuck to your drivers. So keep experimenting, but try some different recordings and see if maybe a buddy had another amp he could bring over, particularly one that is tubed.

Height? I ain't gonna argue wit cha...so you hear your cymbals, violins, brushes on cymbals, etc., on the ceiling? Since those tweeter of yours are 360 degrees: ya hear the same coming from the floor? beats me...

A tweeter radiate 360 degrees in the plane of the front baffle of the speaker unless there is some kind of damping or impediment. Yes, I hear sounds coming from above the speakers. Remember, there is a reflection point on the ceiling also. However, because I have carpet, I don't hear HF sounds coming from the floor.

I agree with Jond. Speaker placement and of course recordings. And I think just swapping components to get it right is the ultimate answer. My experience is limited so I am in part sharing it to also get an answer to the imaging question. So take the following in that context:
I have had two amps an Adcom and now a CJ11. When I switched to to the CJ the soundstage depth greatly increased. You seem to hear more "atmosphere" or venue. However this did seem to reduce the width of the stage-though on most recordings it was more realistic. It is more like actually being in the club as opposed to having the musicians playing in your room.
To clarify- I guess you can say it is like sitting close or sitting far. The further you are... the smaller the image.
Make sense?

specific example...
Spica tc-60 with Adcom. Paul Simon, "Negotiations and Lovesongs". In the room eerie band size imaging. About two feet beyond the outsides of the speakers and a foot or two above. Cymbals high, snare drum middle, bass drum low. Vocals forward of middle. That specific.
AP Virgo with CJ11a, nearfield set up. Speakers really wide apart, really far into room. "Jazz in the Pawnshop" Image starts at speaker plane and goes way back. Real deep. Layered. You can hear the people in the lounge at each table. Big layered. But not much beyond the outsides of the spaekers.