Weren't dragons on the endangered species list in DA:O, having been hunted to extinction by Navarran dragon hunters or something to similar effect?
Dragons were hunted to near-extinction hundreds of years before the current age. The current age is called Dragon Age, because they (more or less) suddenly reappeared at its beginning. So, dragons have been believed extinct for a while, but they are now coming back, and in possibly increasing numbers.
Re Maric. He wasn't actually just from the line of kings, he was the only son (or grandson, a bit fuzzy here) of the monarch deposed by the Frogs. Ergo, rightful king, back on throne.
But yes, there are enough similarities between the two to not have to resort to reductio ad absurdum in an attempt to find them.