I haven't played too many of them, but I managed to pick up Stellaris really quickly. On the other hand, UE4 felt like the type of game you'd only enjoy if you knew exactly what you were doing. I even spent a considerable amount of time trying to learn this game, and most videos i've watched spent like a solid hour rtc performing pre-game setups in the paused state. It's absolutely insane
1000 hour EU4 player here. My pre-unpause setup takes like... 5 minutes, usually. EU4 has a rabbithole of micro you can dive into if trying to powergame, but a pretty reasonable level of success can be achieved without having to ultra-minmax everything.
That's not to say that EU4 is a simple game, by any means, but as the expansions have gone on, the game has power-creeped to a degree, so it's harder to totally lose than it used to be.