I will keep this idea short but informative.
I would love to see a schematic saving and schematic browser for creations that others have done. Not in a sense of decorations or backgrounds. I more so refer to selecting a certain building you've done in your map or level editor. Something like a trigger combination for a new mechanic (Like: You made a slot machine trigger combination), or simply just a house you built and want to share it with others.
They could be uploaded/saved to a public and private browser for personal or public use. And if someone searches for "Slot machine" on the browser as example, it will show all the schematics of (potentially) working slot machines. Or maybe someone searches a big house design for their map? That browser could keep them covered.
I hope you understand what I mean.
Kind regards - Whyme