There are two movies we know for sure are in the Marvel Cinematic Universe’s Phase 4: Guardians of the Galaxy Vol. 3 and Spider-Man: Homecoming 2 (or whatever it will eventually be called). Beyond that, not much is known; they haven’t even greenlit a sequel to Doctor Strange. But aside from sequels, the one property that they really should adapt (and which I believe they have been stealthily leading up to) is Thunderbolts.
Thunderbolts was a comic started in 1997 by Kurt Busiek and Mark Bagley. In the aftermath of Onslaught, when most of the Marvel heroes (including the Avengers) were thought killed, a new superhero team showed up in New York to be the heroes people wanted: the Thunderbolts. Unfortunately, what nobody knew (and was a huge surprise even for the reader at the time) was that the Thunderbolts were actually the supervillain group the Masters of Evil in disguise, led by Baron Zemo as Citizen V.
Eventually, the Thunderbolts kind of realized they liked doing good, got rid of Baron Zemo, and put Hawkeye in charge and became a group of villains trying to redeem themselves. Then the book and team went through various different incarnations, the most popular ones being Warren Ellis’s version (introduced during Civil War), which was a government-sponsored team led by Norman Osborn, made up of super-criminals, and Jeff Parker’s version, which was a team of super-criminals from the Raft led by Luke Cage offering them redemption.
The Thunderbolts, as a concept, works incredibly well. These are not heroes — these are murderers, thieves, and overall villains. Hell, these aren’t even anti-heroes like the Guardians of the Galaxy — the Guardians are many things, but they aren’t cold-blooded killers. Many of the Thunderbolts are and the only reason these murderers work together is because they are forced to do so.
The ones that aren’t forced into doing good are their willingly, trying to redeem their past mistakes and forget about who they used to be. Characters like Melissa Gold (Screaming Mimi/Songbird) and Abner Jenkins (Beetle/MACH-I) haven’t been seen so far in the MCU films — characters who aren’t part of the good/evil spectrum, but somewhere in-between, just trying to figure out what the right thing is to do.
And here is where I think the MCU has been stealthily leading up to this, because there are a few still living villains and upcoming villains that have been a part of the Thunderbolts. The main one being, of course, Baron Zemo, who was last seen at the end of Captain America: Civil War in the custody of the U.N. and probably under the purview of Secretary of State Ross.
In the comics, both Zemo and Ross have actually led the Thunderbolts — Zemo is the one who started the Thunderbolts, while a later team was put together by Ross in order to take out enemies with plausible deniability. The two concepts could be combined for the MCU’s Thunderbolts — in the wake of the Avengers’ war with Thanos, Secretary Ross decides a new, better team should take the Avengers place and forces Zemo to be the team leader, since he is a tactical genius.
Other characters can include Melissa Gold/Songbird (who has been a part of pretty much all incarnations of the Thunderbolts and is a former supervillain-turned-hero), Karla Sofen/Moonstone (a sociopath psychiatrist who is often used to keep team members in place and is considered one of Carol Danvers’ arch-enemies), Ghost (one of Iron Man’s enemies who never takes off their costume; now confirmed to be appearing in Ant-Man and the Wasp), Calvin Zabo/Mister Hyde (a Thor villain who is the father of Daisy Johnson — and I would love if they got Kyle MacLachlan to play the role again as he was wonderfully unhinged), and even the Winter Soldier himself, Bucky Barnes.
Kind of. While some members of the Thunderbolts have been forced to work for them (like Bullseye), others do so willingly, working either as undercover villains or working for redemption. It’s a versatile concept. And, besides, what better why to show up DC then to make a better version of Suicide Squad?