I used a simple square step crown in my kitchen maybe you could do something similar but have the top piece of crown rounded to match your window and door framing. Here's a close up of my crown

I've got simple board and cove on mine, to match my own simple bungalow window and door trim. Sorry, I don't have a better photo on hand, but you get the idea:

Do try to match your current house molding if at all possible. In my experience, compared to the prices that commercial cabinetry companies demand for molding, it's comparatively inexpensive to have matching crown custom cut at a woodshop, as long as you do all of it at once. (They charge one set-up fee no matter how much you'll be having done.) Since you'll be painting your cabinetry (I think?), you can have it made in a more inexpensive wood like pine or alder.

Enjoy! Your plans look lovely so far.

Thanks, I agree that I want to keep the integrity of the existing architecture, and I like both of your options. I do plan on designing it myself.

I used cove moldings. Three different sizes, for ceiling, top and bottom of cabinets.

lanval,
That's a nice simple alternative but with a little bit of flare. I like it.

I'm all about simple yet elegant. Much of my home has a bit of a zen feel to it.

This is in our kitchen.

This is crown molding we used in our guest bedroom. Forgive the low light level. The overhead lighting in our guest bedroom just went on the fritz and we have guests right now so I didn't want to climb over their stuff to open the curtains. But you can get the idea at least.

Jodi-

I actually used baseboard upside down for crown, at the suggestion of my contractor. I wanted to do an even simpler cove molding, but it wouldn't quite cover the gap we needed it to.

lanval, I love what I can see of your kitchen! Do you have more pictures posted somewhere?

Until I saw Badger's, I though this was about as simple as one could get:

Nap101 -- thank you. I had to keep it pretty simple with this tiny kitchen/low ceiling.

jessicaml -- interesting idea about the upside down baseboard!
There may be a few pics of mine around in various topics. No Here's My Kitchen thread, though. Always meant to take some nicer pics, never found time. Maybe I ought to just throw together a post of the pics I have.