Opinions about screen placement

[b40588]

I have a windowless room in my basement that I am putting a home theater in. The room is a rectangle that is 12 1/2 feet by 16 feet. I would like to get thoughts on putting my screen on the long wall or the short wall. I can do it both ways with no problem. My screen is an 82 inch Samsung 4K. If I put the screen on the long wall I can get my right and left speakers out wider. If I put the screen on the short wall I can have the rear speakers back farther behind my seating. I have a 5.1 setup but will expand to a 7.1 or 7.2 setup in the future. Please let me know what you think and I can provide more details if you need. thanks Neil