The beta girls are the most prominent in the deck, with three cards each, because they’re the girls which have the most longevity and presence in Homestuck’s narrative. The alpha girls—Jane, Roxy, and Callie—get two each (with one of Jane’s cards being Nannasprite, and one of Callie’s being her doomed adult self). The central troll girls (Kanaya, Vriska, and Terezi) also get two each, while Aradia (who is more important than Feferi and Nepeta, but not a member of the “core four” trolls) gets one. PM and Snowman (the most important female exiles) each get one, the Condesce (the series’ primary female antagonist) gets one, and Aranea (the most important dancestor) gets one.
If the response to the major arcana is positive, we will expand the project to the minor arcana, and that’s a whole 56 cards to fill, so Nepeta and Feferi and all of the other ancestors/dancestors/carapaces/other minor female characters (perhaps the Beautiful Wonan?) will be incorporated. But the major arcana was decided based on which characters and scenes fit the meanings and symbolism of the cards, as well as to give proportional representation to Homestuck’s most important girls.