The 'rules' you are referring to mostly apply to rock "arrangements" which serve as major garden elements. The effect you are trying to achieve is that of wabi-sabi. The concept of wabi-sabi is difficult to translate into western terms, but, generally, it means to reduce to a kind of elegant simplicity which inspires feelings of calmness, serenity, and 'oneness' with nature which are the feelings we customarily experience when viewing traditional japanese gardens or coffee-table books. Japan is an island group which is about 3/4 mountains. So, for the Japnese, 'nature' reflects the mountains and seascape around them. The effect of wabi-sabi is achieved through the integration of garden plants, stones and ornaments in such a way as to 'distill' the feeling, the mood, of this nature into a very small space. You want to select garden elements which individually and collectively convey an impression of great age, weathered patina, rusticality, and quiet dignity.

For your purposes, you can simplify to a few basic rules that apply to ALL rock placement, including "arrangements":
Select stone that is all the same type, ideally well-weathered granite complete with lichens and/or moss. The patina of weathered stone, the dark color, the 'hardness' of granite softened by the growth of lichens and moss all encourage good wabi-sabi. Using all the same type of stone assures that its use is not jarring to the senses; all fits well and makes a convincing statement. In addition, the seams and cracks in the stones should all run in the same idrection so as to suggest that they are all connected underground and have experienced the passage of time together. The stone should be turned so that its most interesting face is presented though, if it has lichens, it should be turned so that the lichens are facing the same sun exposure as they previously experienced so that they don't die off. It should be buried to its 'spread line' which is its widest point. This assures that it looks stable and seems to have been there forever. So many stones are perched unnaturally on top of the ground and look as if they were eggs laid by dinosaurs! Do not place stones of the same size or shape next to each other. Use the largest stones that you can handle, or combine several smaller ones into a lump that looks as if it were a single stone split by the elements. The use of too-small stones will make your garden look unconvincing and cheapen the effect. Do not obscure the stone with plants but strive to make them weep over the tops or around the sides. Avoid the use of bright colors and too many ornaments .... less is always more in this type of garden!