I need to see the vanity please . In my head that new vanity color does not work with th rest of the space .

I would do an offwhite, enough to contrast the white of the toilet and tub so it looks intentional, not like you were trying to match the whites. What is the lightest color in the tiles?? maybe that color.

Maybe the walls the lightest color from the tiles, and a shower curtain that combines both the blue (like the vanity) with the darkest color from the tiles?

I think matching the tub white for the walls and ceiling is a good idea in a bath this size….the room will be brighter for a nice contrast with accessories…then keep an eye open for a white countertop …on sale it can be affordable for a simple white top…for aesthetics drop the shower curtain down to where it almost touches the floor…

Please post another picture of the vanity, you say it's blue but looks brown in your photo.

Here's a "Before & After" link to a bathroom very similar to yours where they painted the vanity navy blue, off-white walls & white shower curtain.

https://thepalettemuse.com/100-room-challenge-bathroom-reveal/?bathroom=5461369254

Here are my suggestions with what we can see of your bathroom...

- Paint the wall a warm white that coordinates with your tiles

- Paint the vanity in black

- Install a waffle weave white shower curtain and bring it up to the ceiling (long sizes available on Amazon)

- We can't see your mirror but I suggest a round black framed one with a black sconce above (I'm presuming you have an outlet for the lighting above the mirror and not sconces). You can also install sconces it that's possible.

- Framed art on the wall opposite from the vanity

- A mat ( I showone with black, white & beige)