In After Effects, setting the default interpretation for your footage, is a rather archaic process. You have to edit a textfile to do this.
I think it's better and modern to have a 'Learn' button in the footage interpretation dialog:
Set the right interpretation for an item, hit the Learn button and AE adds the new rule automagically to the interpretation rules for the user. All subsequent footage item of the same nature will be interpreted in the way you learned AE.