Sounds awesome!
If you can find a large sheet (or multiple smaller) sheets of cork, you could use various size cards covered with transparent tape (packaging, etc.), and written on with dry erase markers. Certain tapes erase cleaner than others. The tape also serves as a reinforcement for the pushpins which can direct the string. Also, I have found it helpful to fashion some sort of rack to hang empty cards on. I use malleable rubber coated garden wire. You can kind of pin the wire to the board and let the wire jut out through the hole-punches on the card. While a bit wonky, I have grown accustomed to this as part of my workflow although I have upgraded my technique with a few additional adjustments that wouldn’t apply to your use case.
In the end, the weirdness makes it feel like my own and because of that I never felt it necessary to drastically change or improve upon it, especially since I am the only one seeing my boards. Personally, I have multiple types and sets of cards with pre added IDs already on some to optionally be suffixed or prefixed depending upon the circumstance’s context.
And, I keep some of them hole-punched (2 holes at correct distance to be fit onto a 3 ring binder or pegboard). I use these cards to work towards rough storyboards or basic ideation and will often use permanent marker at a certain point since it doesn’t smear when stacked while also still basically erasable with alcohol. Yea, the cards build up a certain messiness (or character) over time, but it adds to the charm. And since these are used very early on in my process, they simply become indications and thumbnails for my paper and digital 2D and 3D blockouts.
It is also good to experiment with the different forms of putty (such as the gray, white, and blue stuff) and just go directly onto the wall depending on the finish, but beware the blue stuff can leave a permanent mark on certain walls in my experience. One consideration you might want to make is bringing additional lighting so you know you can get it just right when that day arrives. Good luck!
Thanks.