Hmmm ... back to the soap holders...
We had one of the ceramic tile shelves put in our ensuite shower, fits three shampoo bottles and an extra large shower gel pump pack. The soap dish underneath the shelf just gets used for razor storage (yes, a foot support in the showerwould probably be a good idea).
Wish we had done the same for the other bathroom, the tiler actually put it in the right place so you can still clean around it (unlike some of those gunky 80's ceramic soap dishes that they always stuck right in the corner). Very handy for something that only costs about $30.