Hello pros, this is the layout for bathtub surround tiling. Will the twin borders look weird or should I use only one line of border tiles? The white tiles will be at the bottom, what do you think compared that to the blue ones? Also my tiles are big, they're 12.5x18, so if the bottom lines with tiles of 9", will that be any problem for the weight on top of it? Thanks very much for your opinions.