Yes it's true that the nature of the shot will override everything else. The positioning of objects within the scene will determine how you approach the shot. Things to consider include whether there are objects that will give good scale cues, do you have a comfortable balance between foreground and background. Don't forget edge of screen issues unless your prepared to use floating windows. Watch how you go from one scene to another, jumping from one depth bracket to another can be jarring. One trick used in many movies is to use a near flat or even 2D shot at the start or end of a scene cuts as this gives the brain a little breathing space.

Generally though you should find that in most instances this fixed angulation - variable I-A method will give a useable result. The art comes from deviating away from this to exaggerate or diminish depth to enhance a scene in a deliberate manner.

Thanks again. I just read your post on CML and chuckled as this forum is exactly where you are sharing that expertise.