The great thing about HoI3 is that the automated AI control for units is actually working. You need to know a few facts about its behaviour, e.g. it needs a LOT of militia or garrision divisions for guard duty behind the frontline or you shouldn't create to wide frontlines because it starts to shift units a lot. But if you give the AI a decent army setup, you can basicially automate everything you want and it will work out. When I am trying new unit builds or general strategies as GER, I basicially automate my army except for tanks and motorized divisions - works totally okay. It also does a fine job in MP games to reduce your pressure. For example, an automated far-east HQ can easily defend against an AI japan, allowing you to put your focus on fighting the german player.
The number of provinces IS high, but it is by far the best change they made to the game. Now you can truly use spearheads, maneuver-warfare and defence-in-depth. I had an amazing MP game as SOV a while ago against human GER + ITA players where I had created a 3-province deep defence line to delay or even halt german spearheads.
There was also some amazing action near Smolensk, where the germans broke through the NW flank of the city and started to encircle it, supported by 3 paratrooper divisions that blocked the swamps NE of the city to prevent my relief units from linking up and halting their spearhead (they also disrupted my supply line, leaving my planes in the city out of fuel for the few crucial days). In the end they got the city, but I was able to evacuate all units with a coordinated counter attack (except for a single outdated tank division that was left behind to "bait" his 2nd spearhead).
That stuff would never have been possible with HoI2. It may seem intimidating, but trust me, once you master HoI3 combat, it is AWESOME. Lastely, the increased number of provinces makes terrain more important (natural bottlenecks), which also makes units like MTN, MAR or ENG brigades much more useful.
As for Sengoku:
I played the demo and didn't like it too much. Bought the game, but only played 2 or 3 rounds. It really lacks reaplayability and covers a way to small timeframe for my taste. I view it as a "test run" for the new engine, where the dev team gathered experience to make CK2 better (and, oh boy, that worked!).
The number of provinces is stupidly high. Meanwhile, every time I look at the Darkest Hour map, I start salivating.
