If you paint that trim between the ceiling & wall white you will totally destroy the whole importance and beauty of the lovely coved ceiling.

What a job to paint all trim white. Please at least leave the crown dark.

I agree with blue. I have a similar older home with 2 coved ceilings with no crown molding. I added picture rails on both. One I stained since the rest of the room's trim was stained. The other room trim was painted. Years ago I had both ceilings wallpapered to resemble metal tiles. I painted/glazed the wallpaper back in my DIY days. Again this was years ago but it still works with style of house.

If you paint the picture rail, will you also paint over the rest of the stained woodwork in the room? A previous owner couldn't decide in some rooms if they wanted to keep the stained trim or paint it, so they painted half the room's trim. They painted the window/door trim and left the baseboards and closet doors stained. It looked silly, so I made the difficult decision to have it all painted. Pls don't rush to paint the trim. Live with it for a while. It looks like your baseboards are about 8", maybe add another layer of picture rail trim to beef up picture rail to be a bit more proportional to baseboards. Painting the trim will really take away the beauty of that era. If you feel the white replacement windows looks odd with the stained trim, once you do the window treatments the windows will fade a

If you are still reading these - what did you end up doing? My ceiling and trim is exactly like yours architecturally. Previous owners had painted the trim a light color. I repainted the trim in a darker shade to accentuate it. It gives a cozier feeling I think, but that is just my personal opinion. A modern look would probably lean toward lighter shades for trims and moldings.

I've always thought about running a strand of soft lighting in the space behind that trim.