The talk earlier about an ending with all the girls being pregnant and your harem gave me an idea. I don't have a problem with whoring the girls out and don't consider it any kind of NTR/cuckolding, plus past a certain number of women I find the idea of a harem stupid anyways. But I think if this game ever gets finished here's my idea for a repeatable two part event.
After you have collected every possible superheroine, recruited all your henchwomen, plus maybe some more civilians like Lois Lane, defeated any rivals you have in both business and supervillainy, possibly have a Luthor for President event, and other events focused around getting more power and/or defeating the superheroes, Lex decides there's just two more things he needs to do to seal his victory: choose a wife and produce an heir. For the first part you pick one of your girls, and leading up to the big day you get a number scenes where you interact with your future bride and other characters. For example if you pick a girl with any king of super powers or high level skills in things like martial arts or magic, certain characters can bring up the fact that a kid with Luthor's brains and money, plus what ever powers/skill it inherited/learned from it's mother would make it the ultimate supervillain in the future. Much like the yacht event every girl get's a her own dress for the wedding plus some sexy lingerie for the honeymoon.
The second part would be the follow up several several months after the wedding/honeymoon with your chosen girl pregnant. This can have another number of scenes like if you chose one of your henchwomen there's a scene of her humiliating her superheroine rival one last time by making her a personal maid, saying she will be on a permanent rotation between the Glamour Slam and Meta Bordello, or that she herself will be married off to to another villain or one of Lex's rich political or business partners as a trophy wife to seal a deal. And of course one last scene of pregnant sex.
But that's just what I would do if I was doing a game like this. Honestly I think events like the prison and the yacht are a great way to get more content past just the whole Glamour Slam/Meta Bordello/cells. Those are all great but I'd like to see more locations in the game.