This does sound like it's generally going to be a lot of improvement, and if it all works as described then I would say it's good news. Personally, I'm not going to let myself get excited until the game's actually out and it turns out to work as described (and actually work, and not be a broken mess), simply based off of Paradox's track record. I also have kind of a gloomy outlook on the game's future as time goes by since they will doubtless be up to the usual jewish DLC bullshit, and in a game so (supposedly) complex, that's likely to be a disaster.
Some concerns I do have, currently:
Bureaucracy and Authority sound like mana. They claim they're not mana, but they were disputing the EUIV "mana" label for a long time, so those could end up being mana too. I hope they won't be.
Reading more details on Interest Groups make them sound a lot like Stellaris' political factions, which were shitty. I was hoping Interest Groups would be a sort of intermediary between pops and parties, and it sounds like that's not what they'll be.
The factory system seems like it's generally being improved, but the lack of automatic factory construction is not good. I would have preferred to see Victoria 2's system as far as construction, expansions, subsidies, etc goes, but with a bit more control over subsidies (such as only subsidizing and always subsidizing a few selected factory types, and never subsidizing others automatically), to avoid the tedium of manually building so many factories.
Now one thing that stands out to me as a huge improvement, mainly because it was a major source of irritation to me in Victoria 2, is the switch away from primary / accepted cultures to variations in terms of acceptance based on language or cultural proximity. I'm hoping this will mean that if you, say, blob into Prussia as the Netherlands, then the north west German pops, while not 100% accepted-culture-equivalent, will be almost on equal standing with your primary Dutch pops, due to speaking a very similar language and having a very similar culture. In Vicky 2 if you did this they would be just as un-integrated with your country as if you'd blobbed into Brazil.