So, I'm going to just ignore the audio completely, as others are already raking you over the coals on this.
Instead, I'm going to rake you over the coals on the projector choice.
It doesn't sound at all like you are distance limited for putting a proper projector on the ceiling, so why in the world are you going with a UST projector?
You lose image sharpness due to the short throw distance, you are using a screen designed for a poor room overall, and you lose contrast with the DLP technology that's currently out there.
A FAR better choice would be to paint the room a darker shade in color, use slightly darker carpet, and paint the ceiling a different color than white. You can keep it a 'rec room' if you want, but then put in a better projector so your 1,000 movies suffer for it. This room sounds ideal for using a Epson 5050 or even stepping up to the JVC RS540 (or better).
The contrast difference will be significant and you won't have all the compromises which UST projectors bring to the table.
Also, 10" to 12" of image diagonal for each foot of viewing distance is the most common. Make sure you don't undersize, or oversize your screen.
But, standard projectors with a white screen should always be the goal. I fully approve of 'exceptions when necessary', but it doesn't sound like you are an exception. You are just making a bad choice in this case. (Tell me if I'm wrong)