Prelim layout and Screen Size (1 Viewer)

[Jeff_Czyz]

I just did a preliminary layout in Visio to get an idea of what I am working with.
My HT will be on the 3rd floor(An unfinished attic.) The ceilling is 8ft and although there is a pitched room, I have 7' 2" of true horizontal space to work with before the pitch takes over.
The dimensions are 16' x 22'. My intention was to have the screen hung from the ceiling. being that I'm only working with 7ft, how will that work if I plan on getting a screen for viewing 16:9 mostly? Can someone recommend the optimal screen size for viewing in this setup?
Here are my rough layouts. http://www.webposter.com/ht The first page shows the wall where the screen will be hanging. It will be in front of the single window.
The second page shows the proposed layout from above. I have some 16:9 dimensions on there.. but I think they are WAY off.
Thanks for the feedback and not minding the all the questions from the newbie

 

[Neil Joseph]

I think you have the right idea. The limiting factor is the 7'4" of ceiling before the pitch. I supposed you could get a little wider if you lower the screen.