I will say that the best overall 'storyline' I have played in a HOI4 mod is doing Changeling Lands > Changelingia > Manehatten Protectorate > ELF > Equestria.
It had a good overall story, that didn't just involve clicking a focus, reading a wall of text and then waiting 70 days for the next wall of text. It remembered that the most important thing about of HOI4, the point of the entire game, warfare.
Playing as the ELF can be a massive uphill battle, so it feels great to progress and take back your country.
TNO sucks in this regard, it should just be a visual novel at this point.