I just hate HOI 3 for beeing an acctual clone of EU 3. Its so obvious, if I let out the map, then there are loads of things where you can see that there is no real difference.
-The cursor (The only difference is the color)
-Occupied provinces (The same thing as in EU 3)
-The spirties (The same one man standing for a whole army)
-Bugs based on EU 3 (You can be at the same time an ally and at war, which could happen in EU 3. Like if 2 nations are at war and both guarantee a country which is attacked will end up being allies still at war).