Most important point, which I assume you have delt with, but just in case - Do you have a recording that has the information needed to create a holographic image? Most recordings do not actually have this information. I use an Opus 3 recording of "Depth of Image", a compilation of exceptionally recorded miscellaneous vocal, small orchestra, solo guitar, etc. The booklet or record jacket tells you what you will/should hear in a well set up system. I first heard this played over a modest, but well set up, system. A group of 4 musicians and you felt you could walk in amongst them and join in.
That said, I have a set up similar in size (9'x10'x9'). My speakers are a bit further out into the room (6'). I located my chair with bass nodes/nulls and high frequencies in mind. I have no sonic room treatments or bass traps, etc, but I do have drapery, big Persian rug, bookcases, etc. I have box speakers and do toe them in a bit. It all works quite well.
Your question re ceiling treatment, I don't think so unless you have an up tilted frequency response you can't deal with in other ways. I looked at your photos and I could imagine all of that equipment on the wall behind the speakers might interfere with imaging potential more than ceiling reflections.
