I agree that you could probably use a bigger screen. The HW50 is a bright projector. Mine is hung about 12 feet from a 106" diagonal screen. The screen is a Carada "Brilliant White" which is a 1.4 gain. On some 2D and at low bulb power it tis almost too bright. I would suggest first that you consider something between 100 and 113, or more if possible.
I am very pleased with the Carada product. I have used this screen with both a Sony vpl-vw50 (ie the Pearl) and now the new HW50es. It is a fixed frame with the black velvet frame cover. It is very reasonably priced for the quality. The slightly higher gain (a neutral gain is 1) helps on 3D content. .
Actually tests have show the BW to be 1.0 - 1.1. so it's almost a neutral gain....