It is interesting to see the parallels between two movies. In HTTYD1, Hiccup assumes that Night Fury is dangerous until proven otherwise. In HTTYD2, Hiccup assumes that Drago is not dangerous until proven otherwise. In HTTYD1, Toothless brings Hiccup the Red Death, and later saves him from it. In HTTYD2, Hiccup brings Toothless to Drago and later saves him from "it".
What’s so interesting about HTTYD 2 is that Hiccup swings too much the other way regarding ideology. As a teenager he wants to be a Viking warrior, realizes dragons don’t need to be fought, and seeks out a more peaceful lifestyle instead. But he swings so far into the peaceful realm that it has its faults, too. Hiccup presses on and tries to speak diplomatically to Drago despite Stoick’s warnings this will not work, that there is no reasoning with such an unreasonable man. The lesson Hiccup learns by the end of HTTYD 2 is that a chief must protect his own. Sometimes that means sticking to peace, and sometimes that means fighting to promote peace later. He has to understand both sides to make the right decisions as chief of Berk.
And the give-and-take of Hiccup and Toothless saving one another is something I’ll never get over. They’re truly equal friends willing to sacrifice themselves for each other. There’s that parallel you mentioned, as well as the parallel within the first movie itself: Hiccup saving Toothless by creating the tail fin, Toothless saving Hiccup when he falls into the Red Death’s flames.