As few tiles as possible in the bathrooms, then it looks best. This completely tiled all the way up is almost as terrible as wallpaper, almost no one does that anymore *shudder*
I can't see anything wrong with it. I would only consider it a "slaughterhouse" if it is very small-scale, inexpensive, and functional. But I also don't understand how anyone could manage to dirty plastered walls in the bathroom.