The rest were either killed in battle or during an underhanded political plot. Study authors from the University of São Paulo’s Institute of Mathematical and Computer Sciences report that only one in four (24.8% out of 69) Western Roman emperors died of natural causes. In fact, three in four appear to have suffered some very painful deaths. Although Italy is home to countless statues honoring the Romans who ascended to the title of Caesar, researchers say only a few of these leaders actually lived to see a long and happy reign. White Walkers would be end game threat and lot of fantasy units are done awesome in Warhammer 2 ( Dragons, Mamoths, Giants, zombies so I don't doubt they can be well implemented.SÃO PAULO, Brazil - As the old saying goes, “it’s good to be king” - unless you were an emperor in ancient Rome, a new study reveals.
I would use similar campaign types like in 1st Medieval ( Start of War of the Five Kings and 1 or 2 later starting Campaigns)
There is also interesting "A Song of Ice and Fire: Tabletop Miniatures Game" by Cmon that shows possible variety in factions, regarding design. There is question if it would be by HBO or book licence, and how to continue after the War of Five Kings, would map consist of only Westeros or would it go all the way to Qarthor or Vaes Dothrak which in my opinion would dilute the action. In my opinion Naval combat would need to be added. That can be only done as separate game, since modding is limited, and from experience bunch of mods are discontinued in Med2 or Attila. Gameplay additions in 3K ( character focused) seem to fit the setting, especially when imagined combined with discontinued Seven Kingdoms mod.