I would try a light blue paint. Do you have an extra floor tile? If so, take it to a couple of paint stores and get a recommendation.

Or a light green. Everything else looks great.

That mirror will not go easily. Be prepared to re-mud the wall. A new light fixture would give a different look. You could do with sconces on either side of the new mirror. A new vanity top might be fun. That sink looks like it could join this century. Hardware changes are super easy and make a statement w/o a lot of fuss.

How about making it moody with some dark wallpaper? Paint the vanity and replace the lighting but only after finding some accent pieces that really pop. Do nothing with the mirror you will need the reflection if you go dark.

I would also want the mirror removed and replaced with a decorative mirror. The light fixture needs to be higher and appears to be upside down. If you don't like the fixture, you can replace that and the hardware A medium sage green paint for the walls. Door hooks for the towels, and art over the toliet. Congrats on your new home.

You could use the middle tone in the tile to paint your walls. That should lessen some of the tile's impact although the wall color now might be close to the middle tone. Someone suggested a dramatic wallpaper. That might not be a bad idea and might draw attention away from the tile. My next suggestion is unorthodox and might not work but you could possibly install a shower curtain even though there is glass shower enclosure. This would hide the shower tile entirely and could easily be opened while the shower is in use.

I always like a watery blue/ green for bathroom walls when there is a lot of brown tones. I would remove the medicine cabinet IMO it makes the room look dated and leave the large mirror there . I like really good lighting in a bathroom so change the ceiling light and the bulbs in the other fixture to make sure all are LED 4000K. Some nice white fluggy towels and bath mats and new hardware.

First step is deciding on a color scheme. For instance, based on your crisp/cozy reference, I chose the ”feel“ below. Then start to drill down to specifics, save ideas and have a plan before moving forward.

For example: based on the above, white walls and vanity (for crispness). First repair walls, as I’d remove towel rack above toilet and add art instead.

Remove small mirror and add a hook for a hand towel and place hook(s) on back of door for turkish bath towels; improving functionality.

Suggest changing faucet, lighting, hardware, as they will change the feel dramatically.

If interested and budget allowed, idea for shower’s floor.

For not a lot of money/effort, your bathroom would be transformed.