Crown Pally gives proficiency bonus to attack. This is worse than advantage in pretty much all cases that matter. Early game its a lot worse, but late game when proficiency bonus is +4 its only slightly worse.
Still worse, but... you can put that on your companions, whereas vengeance pally is self only. Depends on comp whether that's useful, but it does create a use case for crown.
I agree with the rest of your analysis. The new subclasses are mostly for RP.
