But do several elements in the blue gamut.

Idea number 2.

If you do not want to make your walls of bright blue colors, use gray colors to decorate surfaces. But do several elements in the blue gamut. For example, niches or doors in cabinets. You can use some minimalistic design, but dilute it with a bright decor. Even a banal picture on the wall with the image of water will give the most gray room a highlight.