I dont understand why you do so many different types of data. Vector and color is the same type. I understand that if you will change this you will brake backward compatibility, but you can try to reduse types of data and make any automatic migration of old graphs.
Or instant terra will be software not for artist
Vector == color. Color also could be negative value, the same as vector.
I hope you understand what i mean, my english not so perfect i know. But i just try to help you, that is why i am making so many posts on your forum. =)