Light work???
Did you miss the episode when the thing Qyburn built almost killed Drogon? Now that he knows it works I'm sure he's built more and had them placed in strategic positions to take out the dragons when they reach Kings Landing. Remember Cersei's in a defensive position and can stay there which gives her the advantage.
About half the Unsullied are dead. 90% of the Dothrakis are dead. I don't see the Vale getting involved. The wildlings will not get involved either. Only question now is where did Jamie fall in the war to come.
So tell me again how this should be "light work"