Yay, there appears to be a new surge of activity, and just I get back from my vacation. time to get to work.
@ Kiko: I'd have to echo Katluvr, rugs are very good for breaking large spaces up. A nice fleur de lis pattern with a rich color could be very useful. As for the pergola, it really doesn't need to be on a foundation like that. It looks rather peculiar. I understand it'd be a bit of grunt work to remove the foundation and rework the pergola but I really think it'd make a positive impact.
@ ZapKid: Another echo for Katluvr, the barn exterior is very peculiar and falls short of your intended "zen" exterior, and the pitch of the roof is too high.
For the interior, I understand your concern with amping up the color resulting in a loss of "calmness," but if it's too white, it becomes too clinical and sterile in nature. You end up feeling as if you have no business touching anything in fear of some over-zealous avant-garde designer chastising you for leaving smudges. My suggestion is to stick with that nice, unsaturated wood you've got going, but trade out some of the white for creams. Consider wood or an earth tone carpetting for the floor. Overall, making things feel, "touchable."
I feel a note needs to be made about some of the layout choices as well. The computer station needs to be separate from the book-shelves. The desk is disrupting traffic between the shelves, something that's not only inconvenient for the book-browser, but distracting for whomever is trying to use the computer. Try getting it in a corner without a bookshelf facing it.
Secondly, if I'm not mistaken your children's play area is right next to the all age bathroom. Not only does this disrupt traffic to the bathroom but it seems like a very unsuitable place for children. Try moving the door to the bathroom to that adjacent wall, so it attaches to the foyer instead.
