Is that a picture rail with a cove ceiling in the 2nd and 3rd photos? That was exactly the detail I was going to suggest when I saw the first photo (so I guess I was spot-on for the style of the unit?) I think the rooms are fine as is. I don't think ceiling moldings would enhance the cove ceilings. A ceiling medallion for the chandelier might be a nice touch. My MIL had subtle stair-step crown molding in her pre-war home, kind of like this (but vintage).

I don't think that picture frame molding or other fancy moldings would really enhance the space. If you feel you really must do something, board-and-batten V-groove paneling (not beadboard!) below the chair rail might work. Or you could just play with paint and wallpaper. Or you can just let the walls be backdrop to fabulous furnishings.

I would actually remove the lonely chair rail and think art instead of molding since wall molding tends to create issues with hanging art and even placing furniture . I would wait to see what you really need in the spaces the moding can always be added .

I would remove the chair rail. Its not doing that wall any favors. its cutting the wall in half visually thus ”lowering” the ceiling. Maybe a beefier base moulding would add character.

Thank you all I was thinking that because of the complicated wall sizes picture frame mounding may be too distracting as they would need to be many different sizes. I was hoping to focus the detail on the ceiling. I. All of your experience do you think that adding detail to the ceiling lowers the ceiling or makes the ceiling seem higher? I wanted to go with some shade of white for the walls and then maybe stain the floors with a darker wood?

If you're going to change the color of the floors do that before picking your paint color. Paint always comes last. There are a lot of different shades of white (all have some sort of undertone) so you'll want to look at samples next to your floors and whatever furniture you already have before you choose one. If you pay someone else to paint it is expensive and if you DIY you will kick yourself if you spend a lot of effort on it and end up not liking the color. The walls look very clean and unmarked, so hopefully there will not be a lot of prep necessary before painting. You are lucky!

Consider painting wall and trim the same color, different sheens.