Given your stated goal of architectural consistency and the importance of the muntin pattern to the overall look of the house I'd say definitely keep the muntins. You probably won't like the "blank stare" look of undivided windows given a general craftsman theme to the house. In our window shopping it seemed like the jump from Andersen 400 or Integrity to Ultimate was many thousands of dollars, while the SDLs were a matter of hundreds for 30-some windows. (Andersen 400's and Integrity's were about the same price in our shopping, and the Integrity seemed like a much better performing, better built window)

Will you have any window dressings on any of this, or will they all be naked all the time? To me, the drawn alignments in 10:21 (time on the houzz post) looks off. I'd see about a little more header/trim rather than have uneven divided lights as shown in that picture. I know you really want your window trim to match what is elsewhere in the house, but is elsewhere in the house visible from the dining area location? Where will a compromise be less bothering to the eye? To me, if you have divided lights everywhere else, and then unevenly divided lights in the dining area, that is more bothersome than what was originally proposed.

@cpartist - Wow, I think we agree on something... I don't think my architect had muntins in mind, because I did not see them on any of his exterior elevations. I feel like the muntins will definitely tip the house towards the prairie style, which I think would cause us to choose a more earthy/older feel for the interior decorating and finishes. Going without the muntins would instead tip the house towards modern, and have a newer, brighter, more sterile feeling interior. My wife and I are the outdoorsy type, we like camping, hiking, and other outdoor activities. We still are drawn to the clean modern look though...

I do think the first floor windows dictate what you should do in front. In back you can go without muntins, but in front I understand you can get the diamond muntins to snap into the top of the windows, leaving the bottom clear for the view. A dilemma recently just snapped out the diamond muntins they had.