If you want to visually expand your 800 sq. ft. use the Pergo throughout except for the bath. It's so much easier to maintain than tile, I can't imagine why you would want to change for the open concept kitchen area.

Lay the pergo as you would a hardwood. Tile and hardwood have been working side by side for hundreds of years. I like the tile idea for kitchens. I'm always nervous about laminate in kitchens. Pergo is a great name in laminate but you never want to push your luck with these floors.

In N. America we still accept "kitchens and bathrooms" to receive their own flooring choice so I'm not overly concerned with how you've done it. I like that you have been concervative with the kitchen floors. It will work in the long run.

Pretend it is hardwood and run the floor in what ever direction you want. Remember to use expansion joints (transition strips/thresholds) through door ways (like hallway to bedroom transitions).