I really liked the ending... Even though I've been rooting for Dany from the beginning it was hard and frustrating to see her go all Mad Queen on the city. I knew it was over then. I agree that i wish her descent into madness was more thought out.. Wish we could've seen more of the aftermath after Missandei died rather than just Varys saying she hasn't left the room in days.
Read a theory last night that may be a reach but I didn't mind it. That Drogon, being the biggest and most ruthless dragon is actually Khal Drogo reincarnated. They said he flew to the East towards the dothraki, in which he has done multiple times before, and it seems like he knew about the iron throne which is why he destroyed it?
Like I said, it's a reach but a theory I don't mind entertaining.