B&W 800 D4's, Room size, & general Q's

Hey all,

Not sure if this was the appropriate sub-forum, I'm pretty new to all this stuff, and would appreciate any insight you can offer. I am building a new home (almost complete), and leaning towards adding a pair of B&W 800 series D4 to my office. The room is approximately 18'x17'x10'H. Not sure if this makes a difference, but my builder has sound proofed the right side wall where I plan to place the towers in front of (see picture link), as well as the ceiling. I'm not sure what he used to sound proof, but it's behind the dry wall & some wood paneling. In the pic, the "furniture" isn't to scale or anything, just a rough estimate. Link to room pic: https://imgur.com/a/MgpHATC

My questions:

1. For this room size, would the B&W 802 D4 be the correct choice in the 800 series lineup? Or should I go bigger (801 D4) or smaller (803 D4)?
2. Does it matter that my towers will be off center within the room itself?
3. Would it be a waste to spend this much on a sound system when I did not specifically design the room to be used as a hifi listening room?
4. What electronics would you recommend to pair with the B&W's? I was leaning towards all McIntosh.

My max budget is around $100,000 all in for this sound system. B&W 802 D4's + McIntosh would get me to around $50k, and I'd be content spending only that amount. That being said, I'm open to suggestions other than B&W and/or McIntosh electronics (i.e. if there are electronics that pair better with B&W). Thanks in advance!