In the Green Isles dragons are a single species seperated by color and fuction; gold queens, Bronze warriors, Copper builders, and Brass fertile males/philosphers.
all the dragons default to neutral evil, placing their own concerns and wants above all else.
I have introduced a Ln copper guardian of a human city, and a NG bronze (pacifist)
in both cases the alignment defines only its actions, having adopted the roles for personal gain.
The dragons are less intelligent than Core, and very self centered regardless of Alignment.