Another weird Justice archetype I've been running: the "Heal-Tank." Using Great Responsibility and Recuperation on heroes like She Hulk or Vision, it's a game changer. Recuperation, will let you heal 5 when they flip (they flip all the time), although you have to time it with Vision to make sure he's in dense form. Great Responsibility can completely tank a big boost to threat, or to prevent the "when revealed" threat on a side scheme, thus trivializing some of the harder ones. GR is kinda like a minion slayer in that respect, it's a side-scheme slayer, plus it can completely ignore hazard icons... All those side scheme trigger cards are fun to use, and even Pivotal Moment is easy to set up.
I also love adding to Black Widow's Preparation deck. We play 2-4 players on game night, so I always have all decks built for each hero. We grab a hero, grab a villain, and play. If you want to have all the decks built, most "preferred builds" are unattainable without handicapping other heroes. With Black Widow, it's easy to build a strong deck just from extra cards.
Tangential, but I love adding cheap thwart and attack cards for Spider Woman and Gamora to maximize their hero abilities. I even gave Gamora a few Emergency cards :-O because she can trigger every phase, so it's 0 cost to do 1 thwart and 1 damage on the villain phase (I never play solo). It's easy to forget how 1 indirect damage is often very useful --to plink a Tough status or to avoid Retaliate. I've been surprised how well those two handle threat while keeping a steady amount of damage going.
I’ve also been toying with a Wolverine high thwart ally deck. Slap that Mission Training on them to give +1 THW and +2hp and let Wolverine do all the damage with his (amazing) kit and tank the attacks because of his healing factor.
Noob question but if you run cards in the S.H.I.E.L.D War Machine deck that say "Play this card only if you have the S.H.I.E.L.D trait" or "Play this card only if you have the Avenger trait," do you have to be on the respective side to play said cards? Like do you have to be on the War Machine side to play those Avenger cards with that stipulation and the James side to play those S.H.I.E.L.D cards with that stipulation? Or can you play Avenger and S.H.I.E.L.D cards with those stipulations regardless of which side you're on?