As far as the splitting units throughout a region goes, I believe it was likely the solution to how the AI would handle 'guessing' what the player would do. Unlike MTW where provinces one a single whole and entering it would cause the attacker to face all units within that province, in RTW players can feint attacks, do amphibious landings, and simply run around known AI units. Thus the AI tends to scatter its units so the player will have to engage them. You'll notice that once you've entered their territory and attacked something that the AI does tend to quickly gather all the units together to fight you. The AIs actions seem to be a simply solution to a complex problem. (Simple, but definately not strategic)

Overall though I agree with the majority of items on the list.