Hide-a-room features

There have already been several hide things requests, but I thought I would add to this with specificity.

Currently (v 1.6.46), on an existing room, you have the following options:

1. Change the room boundary.
2. Recycle a room.
3. Delete objects from room.
4. Trash a room.
5. Change the skydome when in the room.

Icons for options 2 and 4 appear below the room when you click on the room in the right mode.

I would like to add two features, and also have those features show up in both places.

1. Hide the room contents. If "layers" gets implemented, maybe it can show up within the same tool. The secondary goal is to reduce RAM clutter to improve performance issues on big maps. However, doors and windows should likely stay, since paths of entrance and egress tend to be important.
2. Temporarily retexture the room itself. Three options come to mind. Take as much or as little as you deem fit.
   a. Flat color a room. Now you can have a giant castle with color-coded rooms and say "well, the pink room is the kitchen, but you don't know what's in there until you go there."
   b. Set the alpha of walls and floors and such to 0.
   c. Let the artists minds go wild with the ability to retexture everything, as though you're constructing a simplified floor plan to player characters as a drawn map.