I’d be tempted to get the walls matched to the cabinet - Ace hardware by me will color match with ben moore, it’s always dead on

fwiw I’d also be tempted to get a custom shower curtain mounted close to the ceiling (etsy has tons of them)

Greige is gray-beige. You can't go "gray" with your current floor, vanity and counter.

Can you paint the vanity? The current color looks very pinky-flesh toned.

I would pick a better warm off-white and paint the vanity and walls in that color.

Here are colors that work with your existing finishes.

Not sure why your mirror is not centered on the vanity.

The brass accents on the overly designed light fixture don't seem to work with the casual nature of your bathroom selections.

Consider looking at Sherwin Williams, Accessible Beige. A soft griege shade.

With as expensive and paint has now risen to, you migth be able to get a new granite top cut from scraps for the same price or less.