The bedding appears to me to be a brown figure on a light blue background; is that correct? If so, I would prefer a light brown for the walls (use the grey in the guest room!). Do you have the bedding yet? I recommend waiting until you have it to choose the wall color. They don't have to match but they need to be compatible. For example, brown is brown but a greenish brown (khaki) and a reddish brown may not look right together. Since the hues of paint are more variable than those of anything else, it is usually best to choose fabrics first, then paint. If you can place samples of the paint colors next to the bedding you'll probably be able to choose almost instantly.

I would paint walls and ceiling one color. B.M. Swiss Coffee, a great backdrop for chocolate sofas. Add a rug and the sofa and rug become the focal point, not the walls/ceiling. Add a blue for accent color:

I would do just curtain panels for the bottom windows, in a color that is close to the wall color, in a medium fabric, not sheers. When they blend into the wall color they won't look bottom-heavy; they'll almost disappear. You'll have the softness and the privacy you need without the curtains being obtrusive in any way.

I have 10' ceilings and 96" cabinets. I'm 5'9" and can't reach the top shelves but it bothers me not at all to bring out the aluminum 3-step ladder for the few times I need something (mostly holiday items) from those shelves. Luckily my 6'4" son-in-law loves to cook and does those holiday meals while being able to reach the top. There's not much else on those upper shelves other than wine glasses and some ice buckets; I just sold all of my china and crystal - so liberating !! I didn't want cabinets to the 10' ceiling because of the prohibitive extra cost, the look and also because of the Toll Brothers obligatory useless teensy kitchen windows that are 9.5' up on one wall. The discussion about using glass front cabinets in front of those windows, having to replace the trim around the windows, etc, lasted about 14 seconds. Nope. I insisted on having solid wood tops - 2 ginormous pieces - installed and stained to match because I didn't want to see the unfinished wood when I came down the stairs. Now I see giant dust bunnies and I've decided oh, who cares, lol. It's proven to be an excellent area for some serious art glass that I can't put "out" because of cat and grandchildren but if the house is ever on the market, the little bits of standard greenery will go up there instead. Long way of saying that, even being tall, I still use a stepladder but I think I've had 10' ceilings so many times that I'm used to it.