The Creative Assembly are keeping a lot of plates spinning these days. Not only did they recently release Total War spinoff Thrones of Britannia, but they're still working on Total War: Three Kingdoms and continually updating their Warhammer games, too. They've clearly not forgotten about Total War: Rome 2 either, as they've just released a massive new update adding a major new gameplay element; family trees and the intrigues they spawn.
While characters in Total War games have been able to have children, marry into families or otherwise spawn descendants, the Family Tree screen makes it much clearer. You can track exactly who is related to who, and use that to predict who'll be on your side if your empire splits, secedes or falls into civil war. More interesting is the Intrigues system, which seem to be Crusader Kings-esque interpersonal actions that characters can perform, many requiring certain military ranks, political positions or attributes to carry out.
While the family trees and intrigues are exciting in of themselves, the patch notes are massive and include sweeping changes to the game. Notable tweaks include (but aren't limited to) an overhaul to lighting and water rendering, general graphical improvements, a major rework to agent and general skills (to make them more culture-specific), AI improvements and general strategic balance tweaks.
All of these sweeping changes do come with one major issue: The Ancestral update breaks mod support, and mod creators will have to update their work to the newest version of the game. Creative Assembly do assure that un-modded players should be able to transfer straight into this new version without hassle, and your save games should still function as normal. Any agent who got their skills rebalanced will find their stat points refunded, ready to spend fresh.
The Ancestral update for Total War: Rome 2 is opt-in only at present, so you can find out how to get it in the FAQ here. Creative Assembly also promise that a new DLC announcement is "coming very soon", following up on the semi-recent Empire Divided expansion.