I would go with a very light spa kind of blue. Keep it crisp .. light .. pale blue/white .. nice white towels. Get new pics with white frames ...would go with your painted mirror as well.

I like semi-gloss or even high-gloss paint for bathrooms without windows. It is easier to wipe the moisture off the walls and keep them clean.

we have the exact same situation. the bathroom company advised to change the window to a pvc one with an air vent. but as the winds can be very strong, I am not sure it is a good idea. Any expert advice out there?

See photo of our wc / shower room near living area. The wall mounted toilet frame was initially centred under the window by plumber but then moved very slightly to the right so that the tiling around the window return lined up with tiling around the box out on the left hand side. We now think this looks a bit odd. Also boxing around the frame to the same height as the window seemed like a good idea but now looking at it the shelf looks very deep. Anyone any suggestions about how to make the boxing look better? Our heads are melted. We don’t want to spread the boxed area too close to the shower enclosure on the right as we will have a glass door coming from the right side of shower. Hope this makes sense. Any advice welcome.