Marvel weren't happy to settle for messing with Norse Gods and decided to have a crack at the Greek ones as well, though went for the Roman name. Despite attempts to do the whole Pantheon ol' Herc was the only one to really stick, starting off as a guest ally of Thor before joining up with the Avengers. He ended up as a bit of a loudmouthed buffoon for most of his run and the characterisation's always stuck; to be fair this has led to some decent stories which have more of an old-fashioned adventure feel to them. Occasional attempts to serious him up (a mid-nineties stint in the Avengers when he was clean-shaven, long haired and wore a t-shirt and trousers and looked not a million miles away from Kevin Sorbo for some odd reason) haven't stuck, meaning a regular reversion to Herc the Berk with his beauty sash and knee-high sandals. He's still well under the radar for films and merchandise however, and you can bet when he does show up he'll have a gritty redesign. So no official Minifigure yet then but Penzora has produced a fine custom capturing the key details of the costume, including the strappy sandals and the lion emblem on the chest. Like several with a partial mask he has to make do with a paint application instead of a physical piece but with the right hair it can work in this case. The only other oddness is the use of white legs with heavy painted details; again, I think this is a reflection of Penzora using only official Lego parts, so no plain flesh legs were available (for the record I think the bootleg Speedo Batman might have been the first Minifigure full-stop to use anything close; I've not actually researched that, though).
T'challa of course originally debuted in the pages of Fantastic Four but he's ended up here anyway despite never reaching a particularly gigantic amount of fame as an Avenger, though he's naturally a very important guy as the first mainstream black superhero - an a genius, monarch and cunning fighter rather than lumbering bruiser to boot. That's not bad for Stan Lee at all. Since then the character's maintained moderate visibility - his role as King of Wakanda means he can never stay with the Avengers or anyone else particularly long and despite much effort has never quite made it as a big-selling solo star. A well-received appearance in the Civil War film might have finally pushed him onto the A-list however. It also inspired an official Minifigure which naturally has been bootlegged; also out there are a couple of vintage versions - I'm not sure what they're based on, customs most likely. One has a disappointingly flat head but another has a removable helmet piece which is a little bulbous but does add some serious character; added to some useful detail work like the golden chain around the neck and the end result has just the right amount of Silver Age style to it. However, neither vintage version is particularly easy to find as bootleg figures go.
Though inspired visually by a forties Timely alien hero of the same name the Vision was another one of those things that makes me love the Avengers - created for the book (another o Hank Pym's experiments) and largely staying in place. he's another who was popular on the book but never really made much of a break-out despite some decent character arcs and some interesting powers. He did get to show up in Age of Ultron, however, and got an official Minifigure. This and its' bootleg seem to be the only version out there; it lacks the cleanness of the classic comic look but it's not a million miles off either and the big colours - green body, red head, yellow cloak - are spot-on and it makes it a decent one to settle on.
Dane Whitman is another who spent much of his time with the team, taking over the extant Black Knight mantle from a couple of super-villains. He did get a weird Celtic angle that saw him make appearances with Captain Britain and the Knights of Pendragon and at once point flew a winged horse. An update replaced the Ebony Blade with an energy sword but he's dropped from visibility a bit since the nineties, running in second-tier teams like Heroes for Hire and Excalibur. His powers also lack much interest for Disney and he's another character whose representation is left down to the reliable Penzore. The deep blue scheme works nicely and there's some excellent detail that captures the keypoints of a costume that shifted around a lot over forty-odd years anyway. Even the helmet as a painted head comes off nicely, though I keep meaning to experiment with one of the physical pieces from the Rohan troops from the licenced Hobbit sets. the painted shield is a great piece, however.
Like T'challa, Natasha had been around for a while before she rocked up at Avengers Mansion as one of the goodies. She started out as an antagonist for Iron Man fresh from Soviet Russia before beginning to fall for Hawkeye's charms, giving her a bit of an in to join the team after a gradual coming over which saw dues paid with SHIELD, partnering Daredevil and joining The Champions. She was even briefly team leader. For the films she got to be a generic Joss Whedon action girl, a wisecracking Scarlett Johansson poured into a catsuit to stimulate perverts. The two official figures have leant towards the live action costume with its' silly blue accents but thankfully the bootleggers have done the classic yellow-belted jumpsuit worn for most of her comic adventures - though weirdly they've given her black hair. This is easily resolved, though the figure could do with something to represent the bracelets on her wrists.