I’m thinking not acoustically transparent, but I haven’t completely decided if I want to reuse my discrete speakers or go to new in-walls in the front.

Zero ambient light. This will be a decided basement theater, fully light controlled. It will be carpeted and painted dark (ie matte black ceiling, and dark matte paints). Literally any finishing design aspect can be changed to what’s the most ideal.

The room is smaller than I wanted and, due to entrance orientation, also not the direction I wanted to use it, but it’s going to be approx 18 feet wide and 16 feet deep. Two stepped rows of seating, with full understanding that the front row is going to be closer to screen than ideal (for the kids), and the rear also closer to the rear wall than ideal. Due to the relative closeness I don’t know that 2.35:1 would be appropriate.

Projector location can be anywhere the room. Ceiling is 9 feet and unobstructed. It will be used almost exclusively for movies. Planning a 7.2.4 audio setup.

Budget is… not cheap, not high-end, but somewhat flexible towards well-priced and well-performing products.