As mydreamhome asked, it might depend on how much you want to spend and/or what work you are comfortable doing on your own. Personally, I would replace the faucet with something new and more decorative. I would also replace the towel bar with something metal and more decorative. Since it's a powder room, I might opt for a towel ring or towel bar closer to the sink. (No reason to be using the towel while on the toilet.) You could replace the pedestal sink and/or toilet if you wanted a larger sink or the toilet needs replacement, but from your picture, the current sink looks quite nice. Looks like there are several soaps on the small sink though. Perhaps you could add a decorative (maybe glass?) shelf above the sink or to the left wall (when you're facing the sink). The mirror looks pretty nice. You might consider a framed mirror (though I like this one's oval shape), but I don't know that it's necessary. You could add a decorative backsplash, though if your mom prefers a simple style, it might be too much. You could also paint if you think there's a different color that she would like better. The current paint looks pretty, though it's not very bold. (I mean that in a nice way. I have an all white bathroom that I really like. Just depends on personal preference.) You could also buy some new hand towel(s) and a rug if she likes to have one on the floor. (I prefer to only have a floor bath towel to put down when bathing/showering and no rugs.)

You have options! North side, have shine - powder-coated iron and hand-painted gold finish. This item includes two panels, to hang in a few ways. 2 panels, and each is 24 x 15 x .5” https://www.dotandbo.com/wildorchid/product/designs4comfort-magnolia-storage-ottoman-with-trays-tan-fabric?cacheBuster=1642497158&osky_campaign=end-of-page&osky_content=29

I finally gave up on the trendy indoor plants because I have dry winter air. Your spot is like mine with plenty of light. I got a nice citrus plant from Home Depot at a reasonable price. Mine is Midknight Valencia Orange. It has bloomed each year in the past 3 with that lovely orange blossom scent. No fruit, not enough sun for that. However, it is a very happy plant. It has large glossy dark green leaves. Better performance than many of the "houseplants" I have killed in the past.

I disagree that all your wood has to match. I kept asking my decorator about "matching" wood and she was flat out against it. Said it makes your house look like a furniture ad, and she didn't mean that in a good way. "Matchy-matchy" was her derogatory phrase LOL. Painting your walls, or some of them, would be a good way to bring some life to the room without adding dust-collectors. My vote would be for a soft watery blue-green-gray. For example the SW Sea Salt in this example. https://www.kylieminteriors.ca/8-most-popular-blue-green-paint-colours-mix-sherwin-williams-and-benjamin-moore/