Since the BenQ W1500 produces almost 1600 great looking (calibrated) lumens, you can tackle rooms that others can't really do or can't handle with really good color.
Assuming you plan to be doing some of your viewing in the daytime where you may not have perfect control of window light, then the key is to figure out what screen surface will work best for you (in your budget).
If you have windows to the sides, high contrast gray surfaces, and high gain white screens tend to "reject" that light coming from the sides. Viewing cones aren't as wide, so you are best sitting straight back or not too far to the sides.
If you have budget to work with you can look to expensive screens that are designed to absorb that type of side lighting, so that it has very little affect on the image. Perhaps the best example are the Screen Innovations Black Diamond screens. I'm installing one in my living room in a couple of months, as that room is a nightmare for projectors, and this seems like the screen that will make it work. Unfortunately that's a very expensive screen.
A screen like my old Stewart Firehawk G3 also works really well at handling side ambient light. When you get down to the better known less expensive brands, like Da-lite, Elite Screens, Draper… prices are significantly more affordable, but their screens are less exotic in term of handling ambient lighting, so likely not as effective.
Such screens also help with light reflecting back off of lighter surfaces if that's what you have.
On the other hand, if your lighting is well under control, many swear by white surfaces compared to gray. One reason is that if you saw them side by side in good conditions the white surface is just brighter, so seems to have more punch.
The size of the screen you pair with the W1500 also comes into play. For normal 2D viewing, say a movie at night, you have plenty of power for a 150" diagonal screen, although 3D best viewing size is down around 100" inches with a modest gain screen.
If you have good room lighting control, then the lightness of your surfaces is next in line. The lighter walls and ceiling are, the more reflected light (and less immersion), again, screen can help, but it's less an issue than ambient lighting.
I prefer white surfaces with modest gain. 1.1 to 1.4, for minimal hot spots or appearing darker in the corners. Their issues are extremely minor. On the other hand a high gain screen, upward of 1.8 gain, if you sit straight back, in the center of the cone, can be viable if darker around the edges. It's not my taste, but some folk swear by high gain screens. Hey, it's your show, whatever makes you happy!
In the pictures above, the W1500 handles the significant ambient light coming in from the windows on a sunny day. The image of the football player shows that the picture quality is taking a bit of a hit. However, I do have full room lighting control My screen here is a Stewart Studiotek 130 (a 1.3 gain white surface). It is in no way good at dealing with side ambient light like my old Firehawk could. The Firehawk would show very little sign of light pollution in the same situation.
The screen size being used in the football image is about 98" diagonal, and the image is projected by the W1500 in Calibrated mode. The amount of ambient light hitting the blank screen, and the screen with the football image, is the same, the exposure was adjusted so that the blank screen image gets you a good feel for how the room looked - not very dark at all, while the football player image was taken to show the proper exposure for projected image.