@andre:
The New Miss Marvel is a legacy, but doesn't at all resemble any of the previous women with the name, in personality or powerset.
Ms. Marvel is a very, very rare exception.. and the character she's taking the name from has had a convoluted history of it anyway. The new Blue Beetle is really different too. (and by "new", I mean almost 10 years ago now) But no one outside of comics fans is going to recognize them. Or Squirell Girl, who may be a fan favorite but is incredibly niche. Hell, Iron Man was a C-lister in the public conscious until the movies.
Maybe when the character has been around for more than a year and has made their way into all the cartoons and merchandising, there'll be something to talk about. Otherwise in the meantime, they're overall about as important as the character Gravity.
Some of the new Lantern Corps characters like Saint Walker, Larfleeze, and Atrocitus, and arguably, Kyle Rayner. (though he may not fit your criteria
Green Lanterns are all identical. Same powers, same ways of using them, same public perception. Them being different personalities or species or color doesn't mean anything, anymore than Kid Flash or Red Hulk being different from Flash and Hulk. They're legacy characters, theyre based on the powerset of someone that came around in the 60's, and will never be as iconic or recognized as the ones that came before them… and 99% of the time when there's anything with Green Lantern ever Hal Jordan will be the one used, even if theres been better or more interesting ones since.
Jon Stewart is pretty much the only one that has any chance of breaking the mold because he got so much exposure on the Justie League cartoon, and is a rare black character... but they've pretty much squandered that opportunity by this point... and its still not a NEW character, its a tweak on an old one.
Deadpool really is the most recent break out, and even he took 20 years to do that... before him the only real one that wasn't around at the start of Marvel is what... Wolverine?
Yes, you can point to other X-Men from the period that have permeated like Storm or Colossus or Nightcrawler or Shadow Cat, and they're great characters sure... and iconic, but they aren't going to appear on SNL or get their own movie or even carry their own comic book for longer than a miniseries. (Meanwhile WOlvie had 2 comics, was coming out biweekly, hundreds of issues and cameos so often its a running joke...)
Venom is an 80s or 90s character, I believe and maybe he doesn't count, but Agent Coulson.
Venom is a terrible character, always has been. And while he has become an iconic Spiderman villain, (for some reason) he's not a big deal outside of spiderman. Despite Fox's shortlived plans, he was never going to get to the point of his own movie. WHy? Because the entirety of his appeal is being… wait for it... evil Spiderman. Based of a costume that... SPiderman had. But okay, I'll grant you Venom.
So, Wolverine, Deadpool, and Venom. Is that really it since the 70's? All the big ones were around in the 60's? And the DC ones all before that?
(Even Aquaman probably wouldn't be anything if he hadn't been starting roster in Superfriends.)
Coulson is an odd duck as well. He had a couple really good moments in Avengers that made him memorable, and so then they basically created a terrible tv series for him to carry, but by all rights he was an overblown background character. Yes, it was cute to see him as that guy in the first wave of movies, but no one remembered his name till Avengers... where he worked as audience surrogate.
Understand, I'm not saying good new characters aren't being made... I'm saying there haven't been any breakout truly original ones that can carry their own in multiple media in a long, long time.
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@Below:
What about Gambit? Or Bane? Granted, they aren't AS popular as Harley or Deadpool but I'd think they count for something. Though I am having trouble thinking of any more recent characters (from the last 15 or so years) that have any kind of impact or resonance other than those taking up the mantle of an already established and famous hero.
Gambit happened to be in the comic roster when the 90's cartoon came out, so he was shown to a massive audience and ingrained as important then. But he's never held any real presence in the comics since then despite constant attempts to make him work… his main point of interest was his relationship with Rogue.
Same thing with Jubilee. If she hadn't been on the team right then, she'd be completely swept aside and forgotten... especially considering Boom Boom already had her power and personality, Dazzler had been on the team longer,... and Shadow Cat was already a much, much better character partnered with Wolverine. Nowadays Jubilee is like a non-mutant thats a vampire? Whut? THey have no idea what to do with a very 90's mall-baby... same way no one knows what to do with very 70's Dazzler.
Had the 90's cartoon been made a year or two earlier we'd have a lot more Nightcrawler, Colossus, and Shadowcat. And yes, Dazzler instead of Jubilee. (And they actually did a pilot episode with that roster.) Or possibly a partial New Mutants roster.
A couple years later and we would have probably seen some Gen X kids as regulars.
X-Men Evolution, in 2000, was heavily influenced by the movie roster (hence Toad having a huge role) had a more iconic cast overall.