Beth: here are the ceiling examples. The single slope images seem fairly modern, while the symmetrical images have a more traditional look.
I think this is beautiful, but it may be too contemporary for your house. It is very close to the slope, scale, and proportion you would end up with.
Similar scale and slope.
Pretty straightforward, but would be about the same slope & height.
If we opened up the wall above the hallway, we could have a ceiling something like this. The slope is the same, but the ceiling is much higher than yours.
This could also work with it open above the hall.
About the same slope, up higher
Very similar in slope, height, & proportion to the current scheme.
Also close to current scheme in slope & height
Similar slope in a smaller room
This looks about the same slope/proportion as well, but the ceiling is probably a foot or two higher.
Similar slope, but the walls are about a foot higher. I actually think it is all the glass that makes it feel more open, not the pitch of the ceiling.
A tad steeper slope, but lower walls, so the overall height is about the same.