Ctl3, that´s what I mean too. The Combination of old and new Features. Hoi 4 in the Base-Version wasn´t good in many Parts, that get Fixed with the DLCs Contents in the first important / secondary already. There are many Features from Hoi 2 and 3 already in the Game, which are easy to handle.
1. Hoi 2 Feature: The Decissions you have in Hoi 4 for Political, Industry, Speeches and so on. Not everything was integrated in Hoi 2 or the Hoi 2 Upgrade-Parts.
2. Hoi 2 Feature: Ship- / Tank-Designer you have in Hoi 4. If I remember me correctly back there were only the Ship-Designer for Hoi 2.
3. Hoi 2 or 3 Feature: The Seazones and Duty-Things for Ships in Hoi 4.
4. Hoi 2 / 3 Feature: The Spy System comes back in Hoi 4. It´s much easyer to Handle then in the Predecessors.
5. Hoi 2 / 3 Feature: The Army-Designer for buildup Devisions.
And the Features which get already integrated from both Predecessors which are usefull.
Where I give you all right is the Fact, that Hoi 4 have more Work to do. There are enough old 32 Bit Features which hold back Potential:
1. The R & D-System have to be more polished, esp. with the older R & D-Feature for Ships and Industry.
2. The R & D-System for the Army need much more work, esp. for the Refit for the Airforce, because Navy and Airforce are hanging in that R & D-System too for 80 to 90 % [Aircraft-Engines, Main-Weapons for the Airforce, some Secondary-Weapons for the Navy and so on]
3. The Ministers, Industry-Barons and so on in the Parlament could be have more cool Bonuses / Advantiges and similar
4. An Airforce-Refit with World-Map, Orders, Airzones like for the Ships the Seazones and an Research-System like for the Tanks / Ships.
5. The Realsim of Building up / Restoration the Navy, Airforce and Army.
6. The Integration of Focusses with Decissions and Industry.
And all the Points I don´t have in Mind yet, which are good from the Predecessors and easy to integrate that the 80 % to 90 % Mainstream and the 10 % to 20 % Experts / Veterans are happy with it. The big But is that they are easy to handle. Such Functions were to complex in both Predecessors, why they are getting Shopkeepers or if they get buyed Dust Catchers for the Mainstream-Players.
The Steps with the DLC-Integrations and the Free Patches Inclusions for Modders, Gamers incl. Bugfixes etc. from 1.0.1 up to 1.11.10 Beta are very good Steps forward, but can only the Beginning. The important Steps were the Return of Espionage, Navy-Refit, Army-Refit, Reworked Supply System, Autonomy-System, Officer Corps, Equipment Conversion, Puppet Interactions as well as Focus Trees for the important Nations for Axis, Communist and Democratic Countrys.
Some Focus Trees get missing (like for the Colonys of the already done important Nations) and secondary important Countrys (like Scandinavia, South-America / Africa / Arabia).
The best combination of all I have seen in the Ultra Historical Mod [Focusses, Decissions, Timelines, Industry, Ressources etc.] and for more R & D and Timeline the 1930-Mod from all big Mods I have seen and especially played. Some small / medium ones give good Ideas too to upgrade the Base-Game and DLCs without to much Changes [Real Amount of Tanks, Devisions f. e.].
I don´t miss the Tech-Team-System fully, because with the Indutry-Advisors in Hoi 4 and esp. with the Mod more Advisors [More military Industrial Enterprises] you get an cool Mix of all.