I'm kinda predictable in this: if you ask my opinion on something, I'm gonna do a google search and find pictures for you! I love projects. I love tile, too. My mother in law is redoing her kitchen countertops and backsplash and I can't wait to see how it turns out! She has probably already made all her decisions, but I thought I would throw out some ideas in case she has not.
t the first photo - i like the small squares with slight variation in color, thought she might like that, as well
i am thinking that the mix of shapes in this tile pattern might be nice - could be monochromatic, but have a little interest to it. i think this would work well if all countertops were off white.
again, the mix of rectangles and squares (not in these colors)
more of this idea: the squares of multiple shades of the same color.
and again, but on the diagonal. I also can picture all countertops dark green, the small brick pattern in green, with off-white+green for the diagonal square pattern. actually, I really like this one a lot. I like this sort of "trim piece" look that the brick layer provides.