That was my inspiration for updating the kids' bathroom. This is how it looked when we bought the house. Not bad, but certain elements started annoying me: the checkerboard floor, bleach-spotted Formica, flat-panel drawer fronts, teal and navy accent tile, towel bars that look like plastic...
It's hard to pick my favorite part, but I think the flooring made a big difference. Since the existing tile was in good shape I was able to lay peel & stick vinyl planks over the top. Score it with a knife and snap it off, or use shears to cut rounded edges - pretty easy.
Another big difference was neutralizing the navy and teal accent tiles with Rust-oleum Tub & Tile epoxy paint. I sanded down the shiny tile glaze to give it some tooth, then taped it off and rolled on the paint in one big stripe (right over the grout) with a narrow foam roller. Those are now a bit whiter than the other white tiles on the wall, but they no longer scream for attention. I also rolled this paint on the edges of the vanity cabinet doors and drawers, covering the yellowed melamine edging. (Originally I was planning to add 2" trim strips to each door/drawer for Shaker style, but the cabinet already projects as far forward as the vanity top so I didn't want to give it an underbite).
Weathered wood is popular right now, so in addition to having great flooring options I also found pre-stained rustic lumber to frame out the mirror. A scrap piece became the towel rack along with galvanized dock cleats. The kids actually hang up their towels now.
I added an anchor-shaped towel hook to the left of the sink. How did this house go 19 years without a place to hang a hand towel by the sink? Or knobs to open the drawers? Here are the knobs I chose -- chrome like the faucet, with a rope detail as a subtle nautical element. Other sources...
Shower curtain - HomeGoods
Vanity top paint - Valspar Smoky Pitch (with primer below and shellac over top)
Walls - Valspar Shark Loop (a lighter shade of the vanity top)
Whale and anchor art & anchor hook - Hobby Lobby
Vanity light fixture - Lowe's
Sign on the door - eBay