Look into some grout sealers to take care of that "rusty" problem, or for a solution that's a hair more involved, regrout it! Bags of grout don't cost that much, the guys at the hardware store can give you all the instructions you need, and it's a heck of a lot cheaper than retiling! I think if your grout was in a less contrasty color- not to mention the wiping issue- you'd be much happier with the tile itself.
Also think about painting the frames and cabinet doors a new color and adding hardware, which can completely change the look of the entire kitchen. It'll take you a weekend, but again, a heck of a lot cheaper than replacing the cabinetry.
And for the floors, I don't get the sense that you dislike this particular tile- just the fact that there is so much of it! Plus, a sea of tile in every room can suggest a cold look. So break up all of that with area rugs that work with each other in terms of color, but have different feels to them so that the spaces become more defined and separate.
: ) KC