3) Rey Mysterio

This may look like fantasy booking, but with rumors of Rey Mysterio returning to WWE coming up, this is more of a prediction. Timing is best. After Hell in a Cell PPV, we can have Shinsuke defeating R-Truth and Tye Dillinger in one-on-one matches, before claiming that there is no one left to face him.
He could issue an Open challenge on Smackdown 1000, which would be answered by the returning Mysterio. Mysterio winning the title on Smackdown 1000 would be a great way to get the former World Champion back into the mix.
Cody Rhodes' uncle is a WWE Hall of Famer. More details HERE.
Shinsuke and Mysterio are truly talented wrestlers, who can make this a decent feud. Mysterio can have a short sweet reign as the US Champ, before moving to 205 Live and elevating the Purple Brand.