Republics were great fun in CK2. China and Subsaharan Africa should never have been added.
Nah, adding Subsaharian Africa was great. We got african paganism, more gameplay for Ethiopia and a generally far better Africa map, one which actually matters and ties to the Middle East well.
Also China since Jade Dragon really made the east far more interesting, especially in the earlier start dates. Before it, the East was a Muslim stomp 9/10.
Since then, it became a big China vs Muslims vs Hindus vs Tibetans vs Nomads vs Zoroastrians moshpit and its glorious.