Those aren't spears. Those are probaly more like a Guan dao, Glaive or Bisento. They are staff weapons with a blade on top. Even though they can be thrown, they are seriously unbalanced for an accurate and far reaching throw. Those weapons are used for ranged close combat. In real close proximity they function as regular staff weapons, while at a longer range they cal be used as swords. They are very good weapons for horse mounted soldiers and attacking horse mounted soldiers. Their true strength lies in ranged sweep that would use the full lenght of the staff. But hey it is not as if everyone knows that.
Spears have more symetrical points made for little wind resistance. A spears point is small and simple. If you want to make a throwing spear you should take a look at the Javelin type. The Link sprites look nice.