While not wanting to go too much into tactics that should have been used, all Dany had to do was circle around the ships and get behind them. All of the arrows were pointed forward! She could have burned every ship before they could have turned around.
I'm pretty convinced, now, that Jamie is going to kill Cierci....and then himself. I see him as more of a tragic character, now, then an evil one. While Cierci revels in the mayhem and death that she causes, Jamie seems to hate himself, a bit, over it. He leaves, unwillingly, saying, "I'm hateful!" He is caught in his sisters clutches, and the only way to free himself is for them both to die.

"From our orbital vantage point, we observe an earth without borders, full of peace, beauty and magnificence, and we pray that humanity as a whole can imagine a borderless world as we see it, and strive to live as one in peace."
Astronaut William C. McCool RIP, January 29, 2003 - Space Shuttle Columbia