1. Kurds will have referendum as Barzani said (in an interview with Al-Monitor media website, 23 March) maby between September-October 2016, so it is logical that they are trying to take as much land as they can.
2.Nobody knows what will happen with Kirkuk, who was incorporated in Iraqi Kurdistan in 2014, after ISIS came on scene.
3.I can not find informations about current demographic composition in Kirkuk, but in 1997 :
Arabs - 72 % (544,596)
Kurds - 21 % (155,861)
Turkmens - 7% ( 50, 099)
After agression on Iraq, and overturning of Saddam Hussein, many Kurds came back (many of them were forced to leave becouse of Arabization).
Today almost 20 years have passed, maby today Arabs make 50%, who knows !?
4. Turkey said that will recognize independent Kurdistan, Barzani and Erdogan both fight against PKK/YPG terrorists, and border between Iraqi Kurdistan and teritory in Syria that is controlled by PKK is closed.
Turkey will solve much of her problems on this way and gain strong ally, however Iran will also benefit from independent Kurdistan.
5. Arabs do not have agenda, it seems that they have many land to sell others, they are divided in 15 countries in Asia and maby 7-8 in Africa, so it is not surprise at all that they are helpless.