I once heard someone remark that for CK3 it is better dial back the grand strategy component and dial up the role playing aspect. Not to try to optimize an awesome long-term winning strategy, but to make choices with each ruler along their personality traits.
This may cause you to crash and burn with your kingdom, but it's probably more akin to how humans (and rulers) actually operated.
Ck2 was released roughly 10 years ago amd had tons of extensions.
I played recently ck3 and, even if the vanilla gamw is better than ck2, i got the same dull - boredom after 20 hours than i had when i played vanilla ck2 for thr first time. Give it some time :~)
Crusader Kings 2 and 3 are the only games that have ever recaptured the accidental all-night gaming session for me like Civ I and II did back in the day. Since discovering CK, I can't tell you how many times I innocently started a game on a Saturday night, have my partner come in and say good night... just to have my partner walk in the office and ask when I was going to sleep only to realize it's morning (my office has no windows). God I love it.