Personally I feel tropical brown is a but busy for my tastes buy I'd need to see the other granite and both against your particular cabinets to help you. I'm not a fan of small granite patterns and prefer larger flow. But that's just me. You do not need to match bathroom cabinetry. Go with what you like. Most people will not be goof between your master bath and the other one anyway. And if they do, it still doesn't matter if they're different and adds more character to have different cabinetry in each. I like the idea of a deeper colored front door. We're thinking of doing that for our upcoming build also. It's slightly different than black but not as bright as red. We were thinking of other deep shades also. So I say go for it.

Photos of the space in question would help, since part of my answer would depend on the permanent materials already in place: flooring, countertops, tile, etc. But let me take a stab at this, based on what you have told us so far. 1. In general, light colors, especially cool colors (blues, greens, aquas, lavenders) will make a space look larger, because they appear to 'recede.' White or light gray would work as well. However, if you have dark brown furniture, a pure white will look too stark. You'd probably want something that leans a bit warmer, like Ben Moore OC-117 Simply White or OC-17 White Dove. (assuming again that it works with existing materials) 2. This is totally subjective, and depends partly on how large the home is, and how visible the areas are from a common viewpoint. Too many changes will stop the eye and make a space feel choppy. But an entire white house becomes too bland for most people. Small areas like a powder bath or inside a laundry closet are a fun place to apply some color and break things up. You can also use colorful or patterned drapes in certain areas to add interest. 3. Ceilings can be the same color as the walls, if that color is light enough. If they are very low and light is already limited, keep the ceiling color light or even white. I try to choose a ceiling color that's neutral enough to be used in every room. Choose your wall color first, then you can select a ceiling color accordingly. 4. You CAN mix brown and gray, but would usually need to be either a blue-gray (which Stonington is) or a warmer gray, like BM 856 Silver Satin, or 960 Dove Wing (moving towards greige). You can tie the colors together by bringing in a rug or pillows that combine both hues. As you go forward, don't add any other main furnishings that are dark or brown. You need to introduce contrast with lighter items. Also, decide on an actual color or two that you will use as an accent. Maybe it appears in a lamp, art, small decor items, etc. Otherwise a gray and brown scheme can get dreary.

View of kitchen, family room (with washing machine in the middle!) and adjoining wall. Note: windows still have plastic on them

I think the blue panels are way too high of a contrast in the room; would you consider softening the windows with a blue, white, beige geometric print, but with lined panels to add the darkness you requested for the room? ....another timeless look, is a bamboo styled room darkening or regular shades in the windows in a mid shade relates to the floor color?