While I love painted cabinets, I’m not sure I would paint those. They are a pretty wood(not the horrible golden oak I have). I think a complimentary wallpaper would be fun. It looks like a great spot for a pretty runner.

It would look fine with the same wallpaper. If you prefer a different design, use one that picks up the same tan as the powder room. Often a wallpaper pattern has related patterns in the same colorway.

Your bathroom is lovely and very elegant. It you want to complement (you don’t have to paint cupboards) add wallpaper, update cabinet hardware, a new faucet, lighting and a runner

You could also go in a completely different direction and there are lots of ideas on Pinterest. Consider practical additions like a drying rack, shelves over sink and some lovely tile on sink wall.

I would not paint knotty alder cabinets. (I have them myself.) I think some wallpaper would add a lot of interest like it has in your powder room.