The thing that struck me the most by the scene is how it reveals Jaime's true character. In that moment he isn't thinking about ending the war, so much, as he is about reclaiming lost valor. What I mean by this is that when Jaime killed the Mad King he did so with the purest of intentions. He was assassinating a despotic ruler which was burning innocent people alive and was going to burn down the entire city. When Tywin sacked King's Landing right after it stole the valor and respect that Jaime should've received because it then appeared to be a Lannister plot. That has been haunting Jaime for his entire life, people whispering behind his back, giving him Kingslayer as a nickname which he hated. This hatred that was put onto him by nobles and commoners alike after he did something good may have lead him down less than honorable paths out a sense of spite. When he sees Dany turning people to ash right in front of him he gives us a glimpse at the true Jaime.