Love the mock up, what program you use for that?
Anyways I was going to say don't forget the ceilings first reflection point. As for the 1.5ft thing. Generally it is better but every room is different. you can always test is as your are getting the measurement tools. I like the idea of having the futon behind as well.
Can't wait to see it finished. Before and after measurements would be cool to see as well.
Hope it goes smoothly for you.
