ncleon, I think the surround sound option is going to be difficult for open hall space. Its better to spend all your resources in good stereo with good soundstage, it will give you the necessary spacial feeling when you watch movies with stereo.

You may be surprise to find that there are a group of movies enthusiast who does not believe in centre speaker, they believe that stereo separation for front ends are better. For you maybe you are going to be a victim of circumstances. Just my 2 cents.