Unfortunately the wiring for this was done months ago, and it's set up for a ceiling fixture. No wall sconces for me. Too bad, because I think that would have been a nice solution. The good news is that I did have 3-way wiring put in, at least. At a lighting store today, I was advised to stay away from fixtures that will be difficult when it comes time to replace the light bulb(s). Never would have occurred to me! But other than that, I'm still in the dark (har, har). I wish lighting sites were more like cabinet sites, where you can see the product installed in the room. It's just really hard for me to visualize fixtures in a stairwell, having never paid attention to them before.

I'm facing the same issue in an older house that we just bought. Some ideas might be to add some trim (crown mold, wainscot) or maybe some artwork on that tall narrow wall.

The light fixture just needs to have a little contrast to stand off the windows. I don't think more wood paneling is the ticket here the ceiling is already tongue and groove I would let that stand out as the feature and just paint the back wall. I would probably do dark bronze or black cabinet hardware.

Staircase ideas. you need something on that wall going up the stairs, or both walls, or ceiling. I'd do a pendant light, maybe shiplap or wainscot, diff paint color, perhaps a sisal runner (for that coastal look) and diff spindles, including painting the stairs. let me show you examples. almost identical to yours. painted stairs, handrail, beachy wall color and a sisal runner I like this one. redo the stair treads in a new finish, paint the rest white Painted risers in shades of blues look good w/wood I'd still do a shiplap or some type of wall treatment paint everything else white, stain the handrail a walnut shade. replace railing w/something more modern. diff newl post, glass (but you could do a square spindle) painted steps and shiplap. simple trim molding up the wall. paint the wall at the top of the stairs a diff color, add some interest.