Your post cracks me up! My husband plays. [name]Don[/name]'t you think they might fight over who was more powerful?
I think Sorin is the only one that really screams MTG geek. The other names you could probably get away with. 
I have no idea what that is…so I guess I can’t really say much. I do love all of them except Garruk. [name]Jace[/name] depends on whether its for a girl or a boy, and probably Sorin as well. I prefer the spelling [name]Soren[/name]. Thats just my commentary on the names themselves, I can’t really say much about where they came from.
Maybe your sib set should all come from the same color deck.
I’ve never played the game, but I would just like to throw in that Sorin is a pretty common Romanian name, at least in my family