Scene Local Instances
I have been working on a Local Instance system for S&box that sits somewhere between copy paste and prefabs.
The idea is simple. You build something once, mark it as a Definition, and then place copies of it around the scene. When you change the original, all of the copies update automatically, but each one can still keep its own position and small local quirks. It is meant to solve the "why do I have to fix this same thing fifty times" problem.
Everything stays inside the scene. No external assets, no prefab chains, no cross scene weirdness. Just a live template and a bunch of linked copies.
I am documenting the design and implementation as I go.