Dragons are mostly written as evil in certain tales. I guess it has some old meaning to it. But I don't think they have to be evil.

Warcraft 3? World of Warcraft (WoW)? Those games has Wyverns which looks like a cross between lion, bat and scorpion. :/

I was merely bringing it up as you're uncertain on how big dragons can fly. Wyverns are usually smaller so it might be easier.

I don't think of Wyverns as a source of knowledge. I thinks that dragon with life-spans of a thousand years are more of a source of wisdom than short-lived Wyverns.