Cousin, and aunts are just mediocre incest tier. They are barely blood related and usually a crutch similar to step-something.
I don't get the mother thing, it does nothing to me.
Sister is the get go, someone that close to you that grow up with you, has the same blood and will be forever tied to you no matter what (The Guardian).
Niece and Daughter is the power trip, but I think its bad when the age is too far. Ideal is you impregnate a girl at 16, then at 32 your daughter sees you as a hunky dad etc. The old-young dynamic is a negative for me.