Graphics are nearly always on a white background. Why is this? Have you ever tried to place a logo or graphic on a PowerPoint slide with a colored background? Did you get a white box around it, like the example below? Here’s why. When a graphic is converted to a jpeg, or most other file formats the file, “flattens.” The areas where it was transparent have to be filled in. And it gets filled in with white. Unless you have some kind of image editing software like Photoshop you won’t be able to do much about it. And that is why white rules. If you are setting up a template for others in something like PowerPoint, keep that in mind so that their graphics can still look professional.
The white ceiling thing, there’s nothing to be afraid of. I don’t have a white ceiling in my house. The ceilings are either a light shade of the wall color or a light complementary shade of the wall color. Our bedroom walls are a medium to light purple in the gray family and the ceiling is pale green. It’s quite nice if I say so myself. And my studio/husband’s office is my Mother-in-law’s go to color, a lovely medium warmish gray. The walls and ceiling are this color. It’s neutral but rich and anything hung on the walls look great.