How many people are making food at the same time? How many people are eating in average day at the same time? If one fries bacon do you wish the smell and grease to get to the living room? Do you have animals inside? or small children? Who is cleaning?

The kitchen area is more useful if think the easy access of Fridge-Oven/cooker-sink/dishwasher.

If you live in the area where winter get's cold, I would't place the sink on the "outer" wall because the pipes will freeze. Rather place the sink on that island with cooker and fridge to outer wall. If you live in the warm are, I'll bet you guessed that the fridge shouldn't be in the outer wall :)

Do you gain more efficiency if the laundry room is near to the bedrooms (shorten way to pic up the dirty clothes from the floor) or nearer to the exit (if you dry the clothes outside, if your are coming with dirty clothes home and you want to wash them right away).

The best place for the half bath is next to the exit door. Why? well let's just say, if there is a bad sandwich at the picnic you appreciate the WC to have easy access :)

I hope these helped to arrange the rooms.