For the Crusader Kingdom I'd simply make the requirements and combination of Spiritualist and Militarist.
For Communist Dictatorship it should be available for BOTH oligarchy and dictator authorities, and remove the authoritarian requirement. Just so we can see them in game a little more.

Crusader Kingdom:
Letting go of Authoritarian is not right. Thematically, they fit fanatic authoritarian nicely. However, making it require militaristic as well would make it unavailable to people without mods adding extra ethic points.
In Crusader Kings 2, you can't really call them "militarist" in my opinion. Some kingdoms may be millitarist, but this is not a defining feature of them being a "Crusader Kingdom" in the style of Crusader Kings 2 countries. They are however, spiritualist. That is certain.
Do keep in mind that a crusade is a call to arms in the same manner as inviting war participants through the "Declare War" screen. Further, I see a martial crusade as not a millitarist thing, but a religious one. If you gotta be militarist to enforce your religion by force, does that mean all non-militarist spiritualists are actually pacifists?
Thus I don't see a strong enough arugment to force them to be militarist.

Communist Dictatorship:
I've enbled it for the Dictatorial authority! This also magically applies for the Revolutionary Council personality, because Dictatorial actually has Oligarchic elections.
However, I won't remove the Authoritarian requirement. It's kind of important for a communist regime to have the state and the party control from above.

A thing to generally keep in mind about governments and personalities is that they are not necessarily human, and thus do not necessarily have the same human behavioral traits that make communism or capitalism or fascism or religion into what they are for us.
Communist space cats may actually have a working system of state communism.
Terrifying Aracho-Capitalist spiders may actually have a much better society for such a radical stateless existance.
And so on and so on... So thus, the governments and personalities should embody a society where they work properly.