This is the time you don't try to match things together. You want them to give you the water color you are looking for (plaster and waterline tile). The coping and decking should give your yard the feel you want while looking at what house colors are.
That plaster will give you a fresh, bright blue water color. VERY pretty look. It will not look as dark blue as your design water does. That water line tile will help give the water a pop of slightly darker coloring.
With the waterline tile you will want to go through the boxes and pick out the extra pretty ones to put in the area your eyes fall when you walk out tothe pool. You might also find some not so pretty ones. You will want hide those so they don't get used.
Kim