Joseph could prove an interesting character. I'd almost expect them to meet in Connlaoth or close to the border. I'd almost like to see them meet in a sort of combat scene, though if they happen to be in Serendipity, something more academic might prove better.
As for Samuel, I'm leaning towards Jasper: I've this idea that if he gets near a mordacai, he loses control and starts to go berserk and I'm thinking I might like to setup just how nuts he goes. If you're not in the mood for anime levels of bloodletting, a meeting with Ally is a safer bet.
Anyway, that's four more specific skeletons to choose from. I'm thinking I could pull off one for each of my characters.