Hard to give advice in the abstract -- usually painting a wall is a decision made in the context of the whole room. I agree that the paint isn't doing much with the other things on that wall, but I don't really know what to suggest.

What about taking away things. Not sure if that mirror is necessary. What is going on in this space - more pictures are needed.

That sheen looks terrible on your wall. Not smooth enough base for such a dark color in a semi gloss finish.

When you repaint select a paint in a flat or at the very most an eggshell finish. Here is a softer blue for your walls, and I have turned your mirror vertical.

An oversized mirror, possibly even one that leans against the wall would break up the blue color a bit. In addition, white crown molding would also tone down the color. Not sure what the decor in the rest of the space looks like, but here are 2 examples of oversized leaning mirrors.