Another reason I'm thinking it's Comey -- Mueller's very good friend. By making Comey the first domino to fall, he has a stronger case for granting Comey immunity to flip on others. A clever way to keep his friend out of prison.
Except that why would Comey be charged?
Why would CNN be happy about it?
Look at the scene, not how you want to see it.
This is someone in the admin who is big, and who the media is HAPPY is getting charged. That means someone close to Trump.