A superhero expansion could be really fresh.
I don't think a game pack could fully do it justice, but I think it could be perfect for a full expansion.
It could add a new neighbourhood which has a bit of a 40's/50's city look to it, and adds clothing and furniture in that style as well.
But also adds supersims as a new occult lifestate never seen before in the sims series, which has however flirted with the concept in every single game in the form of outfits, tv shows and all that.
All supersims have core abilities they all share, and more can be obtained but all those extra abilities come with a drawback. You could give your Sim all of them, but that also means they'd have all the drawbacks.
It's always a sensible drawback, like a Sim with super strength breaking everything that can be broken when angry, unable to hold back.
A sim with firepowers can't use them in rain or when wet, and they get angry when wet though can clean themselves with a purifying flame if they don't want to shower.
A sim with mind control powers could at times get more than they bargain for when reading other sims minds, getting debuffs from seeing awkward memories or other stuff they wish they didn't know about.
Most of the extra powers could also be obtained through tech that can be constructed, so Sims could also be a powerless hero using technology. Technology would have the downside of requiring maintenance otherwise it might break if used with a negative effect. Like a sim's mind controll thing blowing up could randomise their own personality traits, and the thing giving fire powers could put them on fire.
A new costume category would be added to the game, which can be used recreationally or as a superhero or villain costume. The technology to use powers could be exclusive to the costume, your sim can't do it in other outfits. There would be plenty of new costumes to match, but everything already in the game that fits the theme of costume would show up here too. Unique to the costume is that you Sim is named by an Alias if wearing it. For example if Clark Kent wears it, he's Superman and will be referenced as Superman in all instances. But if his identity becomes known, he'd show up as Clark kent, Superman when wearing it, showing the player it's no secret.
That would mainly matter for sims in the new active superhero or super villain career though, drawing all kinds of attention they might not want, though depending on traits they may not mind. But any Sim could use the costume in other ways, like a father dressing up as Santa and his kids believing it if the secret identity is kept.
There would be self employed super hero or villain work which would be a rabbit hole thing. The hero can at any time disappear a while to fight crime. Could be combined with a career. They work on their own hours.
But there's also two new active careers where your Sim is part of either a team of heroes or a team of villains. Each has headquarters where other heroes or villains hang out and work on projects, train and all that, and might also disappear briefly during their time there to fight crime as a rabbit hole thing.
Not all would be rabbit hole stuff though, You could have Sims fight in a new superhero brawl option. Can be for friendly sparring, but also a battle that ends with the loser being captured and jailed for a few days until they escape.
And the powers can be used in all kinds of ways, like a Super strong Sim could lift all kinds of stuff to show off, including other sims. A sim with ice powers could also use it for sculptures or creating furniture from it, or keeping their home covered in snow during any season. A sim with mind control powers can make other sims do stuff, but can also learn their secrets. A sim who can fly can show off, can also go explore space and have adventures similar to the rocket adventures, bringing back items and maybe discovering the alien world.
Just saying it has a lot of potential. Could also be fun to see a super sim try to keep it a secret while being a family person. Or maybe the seemingly sweet home maker mother having an evil lair under the house that she tries to keep her children out of and her clueless husband could just be off to his day job.
It also offers room for children playing superheroes, wanting their autograph, admiring a specific hero, being scared of a villain or liking a villain if they have the mean or evil trait. Especially geek sims could geek out over seeing a hero or villain.
