Most players would probably use 1 or 2 skins per mount. Some people would use 1 mount most of the time just because of the look alone. Right now it is about 12000 Gems for all 30 skins, but you can't choose the few you like. ANet could have a bundle per mount type for 2400 Gems; so if I use Gryphon's most, I could buy all Gryphon skins for 2400 Gems Further more ANet could sell individual skins for 700 Gems, making it a better value to buy bundles, but still giving an opportunity for people to just get that 1 skin they really want. This also gives everyone the chance to get all the skins eventually as they earn Gold, or they buy or earn Gems (even tho they will end up paying more for them) Just some ideas of the top of my head.