I’ve never been able to have Skyrim or Witcher 3 click for me, despite trying a few different times (because so many seem to regard them as gold standards of action RPGs, a genre a do like!)
But, to answer your question, for me its probably Stellaris (and, through that, many of the weighty 'paradox games).
I’d always liked games like Civ (Sid Meier’s Alpha Centauri being the first 4x that grabbed me, back in the 90s). But, ‘Paradox games’ were something I tried a few times, and bounced off of every time. They’re just a different beast, in terms of ‘weight’.
But, after having tried Stellaris and bounced off of it, I got talked into playing it multiplayer with some of my friends who play it more regularly, and having a knowledgeable person there to explain some of the weirdness and strategy to me made it all click.
And once I got that down, Crusader Kings and Victoria now were like, understandable to me. Though, I do think Stellaris is my favorite out of the bunch.
This is the way, you sweet summer child