This probably isn't anything new but I really like the TOFOP idea of taking him back to Nakatomi Plaza for an anniversary/memorial thing and basically just following the beats of the first film..
A group of germans now own the building and run their renewable energy research business out of it. It's Tesla mixed with the open plan thinking of Google and it's being updated with all modern security etc. So the new owners are taking pride in, almost boasting that the hostage situation would never happen now.
And you get McClane going back to this building where he became a hero 30 or so years ago and he doesn't really want to go but he's talked in to it by his daughter. He's the same 'everyman' as he was in the first film, he's not a super cop, he's scared s***less half the time but he knows what to do and he never loses his humour. But he's this kinda fish out of water too because he's this sort of 'dinosaur' going back with all his old fashioned attitudes and pre-conceived notions. TOFOP joke that he's going there in his petrol car and he sees everyone plugging their cars in to the mains and at the luncheon he just wants a burger instead of all hip, healthy stuff being served.
Because it's an anniversary thing you get some of the old characters back - Al Powell is there, Thornberg is there (riding the Nakatomi/McClane coattails, trying to sniff out another story), Argyle the limo driver is there (only now he owns the limo business). It would feel a bit hokey 'cos he wasn't involved in the first one but maybe Zeus could be there. Holly is back but they're divorced so she's with someone else now - he's a Greg Kinnear professor type, the 'anti McClane', who just wants to question if force was really necessary to resolve the hostage situation and preach diplomacy. But through the movie she realises she still wants John. You get another smarmy "Hans, bubby, I'm your white knight" type guy trying to do the same thing with the same result.
TOFOP only really have an basic outline of an idea for the bad guys - they're a team of mercenaries brought together by 'big energy' to steal/sabotage the renewable energy... But I think you follow the beat of the first film. The sabotage/protest thing is just a cover. Really, they just want money. The german company are heavily invested in Bitcoin so it's a heist, they're stealing billions of dollars in Bitcoin. And it should be like a heist, they should have an intricate plan just like Hans did in the first film. It would probably be a bit too much to have the leader be one of the Gruber brothers sons but that's an idea..
So you get McClane having to save the day again only things don't quite work like before. Everything is voice activated and there are cameras everywhere so he has trouble getting around the place. Of course he ends up in an air duct again. At one point he needs to get to a lower floor, he sees a hose pipe, he looks out the window, he thinks about it.. and makes a joke about being too old for that.
His daughter overhears one of the mercenaries talking about McClane running around ruining everything and they need to kill him so she goes into 'McClane mode'. You get McClane doing a fair bit of running about and killing but really it's Lucy doing all the heavy action scenes. She might not know what to do, she's obviously scared s***less too but you get John guiding her through it all on walkie talkies.. and I think you can probably work in some tender dramatic moments between the two here, as they discuss him never being there but this is the sort of reason why and he didn't want her to have to do this but he needs her help.
And that should be Bruce's last Die Hard film and you call it "Old Habits Die Hard".
