Good vs Evil
In Mockingjay the whole book is about the fight for humanity and fairness. I would be foolish to think that this book doesnt contain good vs bad as a theme. The whole story is told through Katniss's perspective, as we know she grew up in poverty and lived a poor life, but this whole time all she is fighting for is freedom from the capitol, who is portrayed as Evil. Rebels Vs. The Capitol = Good Vs. Evil
Love Is Essential
Love is a very strong part of the book. It is shown through Families, Friends and lovers all the way through the story. Without love for one another, love for the people and love from the people whom love Katniss she would have failed in succeeding against the capitol
Fight For Power
Through the whole series, Katniss endures through a fight to power against the capitol. As well as there is a good sense as to who appears to have power, and who actually does. Katnss for example lacks power when she is portrayed as the Mockingjay, where as Coin posses all of the power.
Sacrifice
This is a big one. The whole idea of the hunger games is based on sacrifice. All Districts must sacrifice 2 Tributes to fight to the death. Everybody in the series has o make a sacrifice at some point. Like the people of 12 had to sacrifice their homes to escape the capitols bombing. Hell half of the people that we meet in the series fail to stay alive through it to see the glory, as they sacrifice themselves for the cause.