Painted wood floor: fill in any large gouges or scrapes, and sand the entire floor lightly. you can use nearly any paint on the floor, but if you're concerned about it rubbing off with traffic, talk to the people in the paint store/department. you can also get clear acrylic sealer to paint over the floor once it's dried and once cured, it'll protect the paint job.
why not? mixed tiles. I LOVE THIS LOOK, BUT ONE PLACE FOR COLOR TO SHINE UP A TINY HOUSE...FLOOR A GOOD CHOICE, EVEN TEMPOARY, ON PLYWOOD. MARK A SQUARE GRID, PAINT AS INSPIRED A FEW SQ FT AT A TIME. = NEVER HAVE TO LEAVE HOME FOR LONG...
I've never been a fan of tiles on the floors anywhere except the bathroom. I WOULD totally do this from the bathroom floor to join up with the timber in the rest of the house. Even have the timber peeking into the bathroom.