So, 200 turns in, I can't declare war on anybody. I've checked United Planets and I think it might be linked to the pragmatic 'nobody declares war on me for fifty turns'.
Also, despite numerous niggles, it's finally becoming an absorbing 4x for me
. One of those games where i'll complain about 100 things whilst playing for too many hours... 
On another note, Pillars of Eternity is ridiculously good. Glad GalCiv3 is still beta, means i can focus more on Pillars
...