OK....this is how I see it.
- Your screen size and throw distance restricts your choice of Projector to just a few considerations (JVC, Panasonic & Epson) 1st Choice: Panny 8000.*** (lens memory) Second Choice....I suggest the Epson 6020UB.
- At 2.35:1 your maximum screen size is 123" diagonal (48" x 113"). Shift to 16:9 and you'd get 98" diagonal (48" x 85")
- If you can widen the Screen Box opening to 10', then you can fit in some Electric Black Velvet Curtains, triggered to automatically close into the 16:9 formatted sides.
Example of a Panny 8000 installation with Electric Curtains:
- You will need to Black "Out" the bottom of the Screen Box with Black Velvet, because your Screen will be crowding the bottom. One thing you could do is create a "Stepped Look" and raise the top of the center "10' wide Box" an additional 12" higher. There is also another good reason to do that. With a Lens Memory PJ ***, the Lens should be at a level equal to or slightly lower than the top edge of the Screen, and centered as exactly as possible.
- You don't mention / show what lies on the other side of the wall the PJ would mount on / through. But be advised that you will want to invert the PJ so some accommodation for that must be made in the design of any "Thru the Wall" portal. Not really an issue, but definitely required.
- Choose your sound option carefully. The Vaulted Ceiling and almost "square" dimensions will make getting really effective acoustics (especially in 7 Channel) somewhat more difficult.
All in all, the entire project is a excellent one, with loads of potential. Not so thrilled about the Entertainment Cabinet being "White" though....that will make it become a predominant fixture being so big, and grossly over balance the visual effect of the room. Also, it will stand out and distract attention from the Screen during a movie, greatly reducing the immersed and isolated effect one usually pursues.
I deal with Wives a lot.....and I find that given a chance to get really creative yet stick to certain parameters, they can get pretty involved and happy making color choices than make great visual sense and still correspond with necessary considerations. Your room is / will be a Dedicated viewing room, so it only makes sense that anything that can detract from achieving your desired results be avoided.
Suggestion for Colors? Flat Enamel "Mid-Hue" Teal for Cabinet....3x Darker Teal for Walls, very light Flat Teal for Ceiling. All wood Trim (Doors / Base / Windows) should match the Cabinet shade but be done in Satin Enamel.
You could use other Earth Tones like Brown (-ugh-) or Green / Blue-Green (Mo Bedder) Perhaps best would be a medium Flat Gray Enamel on Walls and Satin Enamel on the Cabinet (...blending that big sucker into the environment...)with a slightly lighter shade of the same for all trim.
Those are the "ideas" I would put forth to the Boss, and let her in on as to why. With those suggestions she can substitute other similar color schemes.
....................and here you had to get us started.