I found this photo online, perhaps it will help. In this picture the crown molding on the cabinets flow from the kitchen to the adjoining room. Maintaining continuity with the color and some of the trim detail will make the rooms transition nicely. Don't overlook the details like hardware finish, lighting and plumbing fixtures as these elements can also tie the two styles together. I hope this was helpful.

A nice whitewash wall/paint treatment would brighten it up if done in a light color. Or I would paint it but not sure if all the knots will bleed through? If so then I would use an oil base Kilz to stop bleed through and paint it depending on the interior design I want for each room. I would not paint the ceiling for a more Montana look,

If you think hitting the lamps could be an issue, just move them a bit and add some low accessories (opposite sides to pic below). It's better to have a bit larger lamps and with your ceiling height anything shorter would look skimpy and they don't overwhelm the bedside tables once you balance with something above the bed. Just a thought...if you accessorize your bedding with some soft colors, they will also help to compliment the glass and crystal. You could even change the hardware to a silver.

Pressed metal splashbacks are so rare! This is the first photo I've seen with a splashback like this and I'm really enjoying it.