In the program v. unprogram model, unprograms allow kids more freedom to explore and and discover independently. The "program" model is one where the staff member remains the leader and pretty much keeps the action going through their actions and ongoing presentation. Kids are the audience; the librarian is the leader. The burden of "making it happen" is on the library staffer and the timing can be a little more rigid and librarian-presented. It's more like a storytime and less like your programs.
That said, I agree with you, unprogramming "stations of stuff" can be time consuming to prep if there is alot of pre-cutting/pre-prep - or simpler to prep if kids are given alot of agency to create.
Here's a for instance of a simpler prep I've done. When we crash into a planet and the kids have to go into survival mode (we first talk about what the planet is like - hot or cold; dark or light; windy or calm; sandy or full of plants), I might have three stations - I let a few kids be "medics" to put stickers on "wounds" (at first there are only a few "injuries"; once kids see the stickers, far more wounds are found ;->. Next station is robot hands to grab a cup of legos. Third activity is kids work alone or together to build Lego shelters. Finally we re-gather and kids each talk about their shelters - that's a beautiful imaginative thing! They invent the best stuff to help them survive or live in luxury while waiting for rescue.
I like to look for ways when I do this kind of unprogramming for maximum chances for kids to create and explore so I try to keep the stations focused on giving kids a chance to experiment, build, craft or make. And with all the ideas I have pinned, it's easy to gather just the right stuff to keep planning and prep in perspective.
Sometimes people approach each and every program as an extravagant party that they are hosting. Unprogramming suggests that planning can be less if kids are allowed the time to try things and discover more at their pace.