GridMap is unnecessarily overcomplicated

[ExposedCat]

1. Create a scene
2. Put some models there
3. Export > Meshlib file
4. Link meshlib file to a gridmap
5. Redo 2,3 after any change

Why not just let drop models/scenes right to the panel and let users edit it right there (edit to a unique object will edit all instances)?

Or at least allow to set a scene as a meshlib which will be synced (no need to re-export every time).