Dorsai6,
I like hoop earrings too, but you are wrong that you can't see any other type of earrings on the models.
My favourite Virtuagirl Melisa has a great pair of golden dangle earrings in the "Whipped Cream" card (#582) that in my opinion really add to the show; Kitty Cat has small dangle earrings in "Elegant Angel" (card 1102); and Lucky in "Premium Service" (card 382) has some large stud-type earrings. These are just what I can come up with from a quick check of my meagre collection and the carousel options at present, so if you looked harder I am sure you could find more.
If Totem has a preference at all, I would say it would be for earrings (or jewellery in general) that can be seen in the performance, not something too small to show up, but that's just my guess.