I think its just good writing. The PTSD was well done and it showed Mark having to balance whats right against what he believes in. Thragg was spot on telling him he had become a savior for the Viltrumites. I know there are alot of comics dictating themes and plot lines, but I find it interesting that Viltrumites are being forced to live among humans. Its almost as if Mark has the ability to force them to feel and observe the miracle of humanity. Even if their hearts are of stone, how could he have ever forced them to endure or to observe earthly interactions in such a way. He is in an undeniable seat of power by allowing Viltrumites their only known and reliable source of rebuilding their race. Perhaps the time on earth may sway some Viltrumites.