Paradox hit a real sweet spot with the Clauswitz engine era, EU3-HOI3-Vic2-CK2-EU4.

All the games since then have done a much better job at on-boarding new players but they're all lacking something for anyone who played those previous games. That's not to say that HOI4 or Stellaris or CK3 or EU5 don't have good features but I haven't really gelled with any of them apart from perhaps Stellaris.