maybe you can give dragons a very high gold cost to balance them, something like 800-1100 gold. It might be thematic, after all dragons are known from their love of traesures. They may lend their help to the draconian race for huge soms of gold.
Also you might want to consider a small HP increase to all units/comanders (accompanied by some small increase in cost).
I suppose a draconian race should be physically strong.
looking forward to your complete mod
