What is the importance of the characters' wardrobes in the motion picture, X2?

The film's costume designers apparently referenced the comic book series to guide decisions regarding the characters' clothing and to ensure that it retained each character's essence. For example, in the gothic church, Jean can be seen wearing a jacket with a phoenix embroidered on the back, referring to her comic book X-Name. The letter X is also incorporated in character's outfits and can be spotted on pieces of jewelry and belt buckles.