With 12' ceilings you will need to get a lot of light down to the surface area. You are probably looking at using 90-120PAR bulbs (which have a whiter light). Forget about the windows, they don't help at night when you really need the light.

What type of light are you using over the counter. How much wattage is there? Also, are you going to do undercounter lighting and other indirect lighting?

Recessed lighting in kitchens are usually placed so that they are over the edge of the counter. It would mean that 1/2 of the can would be over the counter and the 1/2 would be on the floor. The rule of thumb is usually placing the cans 4-5' from center. From there you would place the cans as needed. The only place that the light should be directly in the center is over the kitchen sink, if you plan to place one there. This should be on a separate switch so that it can be used when necessary.

Saying all of this, it looks as if you have thoughtfully planned out this kitchen and I would suggest contacting a lighting showroom to find out if they have a designer that can assist you. Your contractor may have a showroom that he is dealing with. If not, check the web for anyone close to you that can give you information on this.

Another source, if you don't have a showroom within driving distance, is to contact a factory that deals in all types of lighting, like a Sea Gull, Progress, Volume, etc. You can call and say that you would like to use their product but are not sure what you will need. Then they will either give you the name of a person to contact nearby or they might even assist you. Many of these factories have technical assistance.

Thank-you for your comments Ilitem. Ironically, we were contacted by my GC's lighting subcontractor this afternoon. I will meet with him later this week and take your comments with me when I see him.
I have put so much time and energy into the layout of my kitchen, even to the point of where I put the spoons and towels. The one thing I would do differently is to focus more on the lighting of these plans, vice thinking the "normal lighting setup" would be sufficent. I have a lot to learn!
Thanks again for your help.