I was the other vote for Dani Moonstar, both for her as an individual character and also as a kind of stand in for the Claremont created New Mutants generally (although I also voted for a few more of them). One thing that's great about the original New Mutants as a team that marks them as part of the trends in the height of the Claremont/Simonson era is their diversity of backgrounds and the limitations in their power sets.
Sunspot can briefly be super strong
if he has recently been in the sun, but it doesn't come with any kind of invulnerability so he's just as fragile as any teenager.
Cannonball can be invulnerable,
only while flying more or less uncontrollably and he can barely turn.
Karma can possess one person at a time, while losing the ability to do anything her own body while she does it. (Definitely the most powerful, but in practice it means they have to face problems more complicated than one (1) human or humanoid villain.)
Wolfsbane can be a girl, a wolf, or a wolfgirl.
Mirage/Psyche/Moonstar is introduced as the least conventionally useful of them all in standard superhero combat situations: She can create illusions that she can barely control, at times accidentally exposing her teammates' most traumatic memories or deepest desires. It's a very blunt storytelling device, but it's a good one for a book about the relationships and emotions of teenagers. And Moonstar is the character who is the protagonist of the book and becomes co-leader of the team, even when it gets a few more conventionally powerful members. Alongside a de-powered Storm, Moonstar creates a broader trend in Claremont's work of teams being lead a woman who was essentially a normal human in a conventional fight and who gains that position by defeating a symbol of the boring 60s X-Men—a depowered Storm defeats Cyclops in a one on one duel, and Moonstar keeps the team safe from a Brood Queen possessed Xavier in the first three issues of New Mutants.
Moonstar herself is also in a way the villain in that initial New Mutants story, as the team travels through her illusions that are operating on an enormous scale. It suggests a long arc for the character's power set that was unfortunately never realized. The extreme 90s flattened the characterful power sets of Claremont/Simonson characters and replaced them with what could easily be drawn on a splash page, and this was especially true for this cohort of characters. Boom-boom does time bombs? No, now she does pink energy blasts. Richter does vibrations? Now he does green energy blasts. Sunspot has temporary super strength? Now he does black energy blasts. Even Cannonball, who has the classical superhero power of flying into a guy to hit them really hard, had a period where he was doing yellow energy blasts! .And Moonstar, a protagonist with a psychological and character driven power, became a tertiary character who shot arrow shaped energy blasts.
Dani recovered from this sidelining and flattening somewhat in the following decades, but never fully reclaimed the spotlight and rarely became a fully realized character. But, when she was in the spotlight, Dani's conversations with her teammates were the core of the New Mutants, and her power set was part of a move toward superhero storytelling that didn't have to center violence.
One example of this is the introduction of Legion, Xavier's more or less omnipotent son with multiple personalities, each with their own power. Xavier, Legion's mother Gabrielle, Dani, and some others are trapped inside Legion's psychic landscape. It's Dani (along with fellow New Mutant Rahne) who sees through the facade of the swaggering good guy persona of Jack Wayne and seeks an uneasy and imperfect resolution with the Palestinian terrorist Jemail (ambiguously either the absorbed psychic residue of the man who killed Legion's Israeli stepfather, or Legion's perfect psychic mimicry of Jemail), who turns out to be the only personality actively working in Legion's best interests. It's blunt and imperfect, but also it's a story that explores the humanity of not just a Palestinian caught in the crossfire, but of a Palestinian driven to terrorism. It's a comic where a holocaust survivor lashes out at a Palestinian terrorist who killed her Israeli husband, and that action is portrayed as an extension of cowboy-imperialism. Dani is only one character in this complex story about cycles of violence, but she is the kind of character who exists to tell this kind of narrative. It's not exactly
The Battle for Algiers and it's definitely raw and messy, but it's nonetheless presenting a perspective you don't see often in mainstream American pop culture.
The conservative and backwards looking 90s and current anodyne corporatism of Disney Marvel aren't great for a character like Dani. She's got more focus recently, but I think she's still essentially a character meant for a path not taken and now forclosed, a suggestion never realized. Or, if you're more optimistic than me, maybe she was ahead of her time and Marvel is finally catching up.
Either way, Dani Moonstar was the future.