I have finished the Vanguard campaign, and I was rather disappointed that I won it via just allying people. I was gearing up for a war while securing myself allies and then all of a sudden it was GG you won.
Greatly enjoyed it before that point.
Right now I am midway through the first Kir'ko mission and loving it. I am at war with one of the Vanguard nations and another Kir'ko nation and it's going fantastically. Having to fight on 2 fronts while also trying to expand towards the objective is thrilling.
It surprised me, too, as usually I am not a fan of playing bug races and of all of the Planetfall races I still think that aesthetically the Kir'ko are my least favourite. Campaign is great though.