I think that there should be a few 'official' dragon types added to the ones you have already made :3
Lesser dragons:
Dragons with no particular special ability, can merly fly, or really anything with claws and a tail
Wyverns should fall into this category.
Dark dragons:
A dark dragon by choice, not necessarily evil, not necessarily good. They keep to themselves, and are very biased towards everything. Any dragon can become a dark dragon by simply removing themselves from the world.
Earth dragons:
Stone dragons, sand dragons, ect.
These dragons should always be very sturdily built, strong, and docile. They can hide very easily, and are plated with rock-like scales.
Sand dragons should be of a lighter build, and long, thin scales, like on a snakes belly, can burrow in the sand.
Jungle dragons:
Jungle dragons may fall into a lesser dragon category, unless they have something particularly special about them. So basically, lesser dragons that blend into jungle/wooded areas better. Should be very agile, and keep to themselves, but very mischievous when a human wonders by :3
Whisper dragons:
Lesser dragons may fall into this category, along with wind dragons, sonic, nova, really anything but earth. They are EXTREMELY quiet and keep to themselves at all costs, many dont know that they are ever there. They should be able to control sound/ect.
If any 'power' they should have, it should be invisibility. They should be very peaceful, and awkward in a conversation. When confronted, they should 'teleport' away. :3 (By teleport, I mean use whatever skill they have to flee, like wind dragons maybe make some smoke, sonic dragons flash some light, blinding, ect.)
That is about it for now. :3
I hope you like my ideas ^^