Hm. I tried to play the game using the Dragon-as-natural-member-of-ecosystem model: as a super predator (such as lions) having to live in a symbiotic relationship with prey. But the game doesn't seem to support that style of motivation. pft.

And as for princesses: Queens and princesses actually have more political power than kings and princes -- kings and princes may fight in crusades, but it's the princesses and queens who do all the diplomacy, and political maneuvering. So losing a princess is a greater risk to a kingdom than losing a prince, therefore, a princess is a more important bargaining chip.

(also, I wanted feathery wings -- and wasn't given that choice!)