If we look at GRRMs original pitch for ASOIAF Jon was to fall in love with Arya (those who think Jon/Dany is creepy count yourself lucky!) but later Tyrion would also fall in (one way) love with her. This then was to drive a wedge between Jon and Tyrion. If we consider the incest of Jon and Arya was replaced with Jon and Dany - was Tyrions creeping outside the ship room nothing more than jealousy? And is this what will complicate the Targaryen powerhouse that is being created for the next chapter?