That is why I am starting to think this is going to end with Tyrion (currently 2nd in line of Baratheon succession behind Cersei and Jaime) on the throne, bringing peace to the realm with his long-ago marriage to Sansa Stark, and Dany either sacrificing herself or not taking the throne at all. I can also see the Seven Kingdoms ending up splintered again as a result of this; it isn't like the North is going to bend the knee to King' Landing ever again.
I am also starting to think that something bad is going to happen to Dany en route to Westeros or shortly after she gets there; I mean, it is too easy if she lands with an army 5x the size or more of everything else left in Westeros. She would just roflstomp everyone and it can't be that easy...though the only things I can think of that would really screw her are either a hurricane, or Euron attacks her in force and demolishes most of her fleet - she does have Theon and Yara after all and has thrown in with them to overthrow Euron. Or, maybe she takes King's Landing and while her horde of Dothraki is raping and pillaging Cersei executes the Aerys Solution and blows up the whole damn thing, thus evening out the playing field a bit.