I don’t see any reason that all hard earned skins unlocked by your characters shouldn’t be stored on the HoM vendor with the rest of the heritage skins. Most skins are a real pain in the greaves to get, they should be able to be shared between your characters and easily retrieved.
It’s strange to me that ANet would have such elegant solutions to most of the game’s issues and then put in this incredibly stingy skin system. The money grab of transmutation stones can’t be that important. Especially when they are forcing people to buy keys for the fused skins.