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.

Ikea has some that i use often they come in different sizes.

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.

Thanks very much for all your feedback. Just to answer a few queries - the deck is directly outside the main room so the new doors open out onto it. The doors won't be French - they're just the only doors that the 3D planner I'm using had, they'll actually be large stacking doors. I've had another idea too which would be a lot more expensive but offers a completely different approach. This is quite rushed so doesn't show accurate layout of kitchen or anything like that, basically just provides an idea. Thoughts!?