I don't think a 1.3 gain is going to help much. The best way is to "trick" the lighting. If you have overhead lights in one corner that are spotlights sunk into the ceiling, they should shine straight down and illuminate your guests without casting much light on the screen. Another trick would be to darken the walls in that area to absorb more light. I have two spots over the audience area of my crt projector, and people can actually read from them while watching the screen without it being marginally washed out. If you can't sink a spot into the ceiling, there are ones that attached to the outside and can be directed down that work just as well. A very dark carpet will also help. Avoid florescent lights as they cast too much green light and will throw the color temperature off. This has been my experience in over 25 years of working with dim giant screen TVs in the past.