Not exactly a buffcup themed idea âŚ.. but have you ever thought about how Fishlegs and the twins are kind of foils to Hiccup character wise? Like, Fishlegs is a huge nerd (affectionate) to the point he speaks/shouts dragon statistics out loud instead of hiding or something during dragon-fighting training. Still he doesnât seem to suffer socially or otherwise for preferring to cultivate brains over brawns, like hiccup seems to, probably because Fishlegs is pretty big.
And then thereâs the twins !! I donât know if this was shown in the movie (or if itâs something developed later in the tv series). But ruffnut and tuffnut are infamous for being prankesters and causing trouble, kind of like Hiccup was at the beginning of the movie, albeit non-intentionally on the haddock part. And yet Stoick says âif you donât wanna go on the expedition, you have to watch hiccupâ which immediately gets most of the other vikings to agree on searching for the nest âŚâŚ. not tuffnut and ruffnut who like to cause problems on purpose.
Story-wise you could argue that those parallels werenât intentional and the creators just wanted to have a more well-rounded cast design and personality wise, since Snotlout and Astrid kind of already filled the classic viking roles (albeit from different perspectives).
But headcannon-wise and conceptually ?? This is great food for thought >;D !! Like, Iâve been thinking about what you said and the box Hiccup got pushed into. Itâs not the same thing, but it kinda reminds me of how marginalized people (someone of a minority or with a disability) can often be judged more harshly than others, even though they essentially do the same thing. Like someone can do A and get away with a slap on the wrist or some gruff remark, but if hiccup does it ? Itâs a way bigger deal and so is the admonishment he gets. What do you think about that ? Because thatâs what sets him apart from fishlegs and the twins, the fact heâs considered to be a runt by berk.
I think the general design philosophy the makers of httyd 1 tried to follow with the side characters is that they took an aspect of Hiccup's layered character, and made it the defining characteristic of said side character. Fishlegs for example is Hiccup's nerdy side, taken to an extreme that even Hiccup gets annoyed at at one point, when their facing the zippleback in dragon training.
Snot is Hiccup' need to prove himself, as well as Hiccup's crush taken to an extreme, hence his rather...performative speeches about how he will avenge Gobber's missing limbs.
I could argue that the twins are Hiccup's destructive tendancy, as well as his defiance, only they do it for the love of the game, but this was indeed something developed in the show's rather than the movie, so I think it's like you said, it was probably done to have a more well rounded cast of characters.
Interestingly, I've seen a couple of fics where the twins do respect Hiccup's ability to cause destruction. I've also read and quite liked a few fics where the twins would bypass Hiccups cautious nature and do bring out the prankster in him, and they'd go round causing some harmless pranks.
I think the thing that sets Hiccup apart from Berk, and make the ire he receives from Berk more severe are two things.
1. People will hold their heir to a higher standard that a random person. The future ruler of the island being even a little irresponsible is far more severe than another person being very irresponsible, because the heir will rule in the future, his action will affect many lives. Furthermore, from what we're shown, the Haddocks have always been prime examples of the Viking Way, so much so that the concept of the Viking way has become so ingrained in Stoick he can't really think of another way unless radical stuff happens. For years, the Haddock lineage has always managed to meet the demands the difficulty life of Berk has demanded from them, and Hiccup is the first Haddock unable to meet those standards, and he doesn't meet that by a looong shot, not just a little, so perhaps that disappointing people, hence their harsh treatment of him.
2. People expect the twins to mess around with stuff, they know they do it for the love of the game, and pre dragons, realistically, the twins worst pranks would be some sort of slapstick stuff or them beating the everliving shit out of eachother at inconvenient times (ex. A fucking Gronckle is charging at them in the middle of dragon training), and the twins are in terms of attitude, way more Viking like than Hiccup, so maybe that earns them some redemption in the eyes of Berk. Hiccup meanwhile, is doing it because of an increasingly hopeless cause of wanting to (in the eyes of Berk, selfishly) prove himself to his dad. There's no doubt that perhaps the people of Berk are a little bitter towards Hiccup for that.