I've made posts about this before but I want to write in more detail why I feel like the second HTTYD film is less thematically consistent than the first, and what changes I would make to address that.
One of the reasons I love the first movie is because it always seemed to me to be first and foremost a movie about identity and being true to oneself. The main conflict, or at least one of the main conflicts, is Hiccup having to choose between: A) the life he always thought he wanted, which comes with social acceptance but requires him to reject who he really is; or B) a life where he defines his identity but risks social rejection from his father and his community.
Ultimately he chooses option B, and luckily for him, the people around him change to realize that Hiccup’s real identity doesn’t have to be rejected, but can be accepted and even change how they see themselves and the world. (Which is why I believe this movie appeals so strongly to viewers who are neurodivergent and/or queer…and as a deconstructed Christian/agnostic with strict parents, this movie really hit home for religious reasons as well.)
There are other plot lines in the film too — like the grown ups trying to find the dragon lair (which directly leads to Hiccup being able to show that his way of interacting with dragons can protect the community) and Astrid’s one-sided rivalry-turned romance with Hiccup (which highlights Hiccup’s discomfort with his new popular role and then later on provides him with an ally who can help save their parents and the dragons). These smaller plot lines help to strengthen the main plot and don’t distract too much from it (although I know there are criticisms about the way Hiccup and Astrid’s romance was written, both in this movie and the franchise as a whole. I think a lot of it is valid but IMO it at least doesn’t detract majorly from the main theme of the first movie).
Following that, we have HTTYD 2. We start with a restless, lost Hiccup who doesn’t know what his future holds but knows that he feels stifled by expectations to be chieftain. The movie unfortunately doesn’t go very far with this. We see him have the title of chieftain put upon him before he’s ready, due to Stoick’s death….and there doesn’t seem to be any tension afterwards. In fact after Stoick’s funeral, we don’t really see Hiccup struggle with his role or his grief in the second or third movie.
Another major plot line is Hiccup’s relationship with his mother. There’s a lot of possibility here to explore conflicting feelings of bitterness and a desire to rekindle their relationship…but this also doesn’t go anywhere. Hiccup immediately forgives his mother for not trying to return to him, and their relationship is smooth-sailing for the rest of the movie and in the third as well.
Finally, we have the plot line with Drago, which does three major things. 1) it leads to Stoick’s death (already discussed); 2) it reinforces the bond between Hiccup and Toothless when they overcome the power of the Alpha's control (very powerful and emotionally moving...I love this moment and I think it's a great parallel to the hand scene in the first movie); and 3) it provides a foil for Hiccup (which is also super interesting but sort of lackluster in comparison to Viggo, who was a more fleshed out character)
I think all of these plot lines are interesting, but because they don’t do very much to enrich each other, they sort of just happen sequentially without enough connective tissue to make any of them as strong as they could be.
I’ve mentioned before that I would prefer the plot of the second movie to be extended into two, with Valka being an antagonist (as she was originally planned to be) in the second and Drago being the main villain of the third movie. Here’s how I would do it:
The second movie should continue the focus of Hiccup’s listlessness and search for a new, more fulfilling identity. Meeting his mother should present him with a new choice, somewhat like the choice he had in the first movie. He could abandon his old life and his responsibilities and stay with his mother, living more freely (but perhaps being pressured to do morally questionable things for what she thinks is the greater good), or he could remain with his father and community but feel stifled by their expectations.
I don’t have the particular events figured out, but I think it would be narratively satisfying if Hiccup’s choice is once again a middle point between extremes. Maybe he does become chieftain, but he finds ways to share the pressure with his friends and community so that it doesn’t overwhelm him. Or maybe he abdicates his position as chief to someone else (cough Astrid cough) but still remains part of the community while having time to explore and live life the way he wants to. (Also at some point in there, Valka has a redemption arc? Maybe after Stoick’s death?…Something like her actions put him in danger and then she has to re-evaluate if she can continue to justify the choices she makes, idk still workshopping)
I do think Drago should be alluded to or even appear and cause chaos in the second movie (maybe Stoick's death is still tied to him in some way?), but mostly to build up tension and suspense so that when he’s properly introduced in the third movie, it’s after a lot of anticipation and fear.
Then the third movie could be wholly devoted to two things: Hiccup dealing with his father’s death, and Hiccup dealing with Drago. And these two things should be strongly related. I think it would be really fascinating if in his grief, he finds himself becoming more and more like Drago — more cruel and willing to do whatever it takes to seek revenge. Then he would have another choice on his hands — does he become like the very man he wants to seek revenge against, or does he stay true to himself and find healthier ways to heal from his grief and trauma? Again I don’t have particular events figured out, but Toothless and Hiccup's friends should be an integral part to all of this. Like I imagine Hiccup increasingly putting Toothless and the other riders in dangerous/exhausting situations trying to find Drago…only to realize that he’s mistreating them in a way very similar to how Drago mistreats his dragons and soldiers. I think that would be very powerful.
So yeah, that’s how I would change the franchise. Still three movies, but with more intention in how the themes are explored.
I feel like…I’ve just given myself more fanfiction homework, lol. I do think it would be fun to write these at some point. Once I’m finished the major fic I’m already working on.