After hours and hours of thought, I have finally found a way to explain this.
I was playing Garry's Mod, and I realised that my old idea was similar to the Spawnlists, and how you could edit it in-game.

Sometimes, I feel that how Add-On creators set up bricks in the Brick Selector is quite annoying. I would change the script of bricks to change their placement of them, but it's quite annoying because every time it gets updated again, I would need to change it again.
I feel that a secondary window should be made for the Brick Selector, which would allow you to change the placement of any bricks, and also allow you to add new sections and categories or even remove them. It would also allow you to apply new icons to bricks, and even save your changes.
I would love this so much.
You could rearrange EVERYTHING. That means not just bricks, but the brick groups (1x, 2x, 5x height, etc etc) and the tabs too.