Love me some Stellaris, I keep coming back to it. I tried to start some other Paradox games like HOI4 and EU4, but unfortunately it just doesn't click for me yet :(
If you wanna play multiplayer eu4 sometime, I can show you the ropes. Lots of stuff going on at once, but half the battle is just knowing what you can ignore until later.
Yes it’s quite active from what I’ve seen. AOE4 and AOE3 DE are my two main games at the moment and I never have trouble populating a lobby, even at weird hours.
CK3 took me a little while to warm up to as well. Had to force myself through a couple games. It took me a bit to actually understand the mechanics of how the game works, but I think once it really starts to click, you'll have more fun with it.