Display Backgrounds - Plan of Attack!

I am starting to get serious about designing great toy displays. I want to be able to set up a collection to look like a catalog picture, or better. See this post for more details. The project would involve the creation of backgrounds and display props that I can set up and rearrange to suit whichever toy I am displaying at the moment.

I have been gathering prop parts for a few years now, just throwing them in a box until I am ready. Here's some of what I have thus far:

Various tree parts that could be painted different pastels for Lady Lovely Locks or Forest of Feelings. They could also be joined and kept their original color for My Little Pony displays or anything else that might have a tree in the background.

A cloud base. Not sure where this came from. I came upon it on eBay a few years back. Good for Care Bears, Moon Dreamers, My Little Pony, etc.

A few other small parts.

As far as the background goes, I have an idea in mind. I will create layers of background that can be switched and matched around to suit the toy.

The first layer would be a gradient sky. Something like these:

I would also do a dark starry night sky for things like Moondreamers and My Little Pony Pegusi and Care Bears.

Then I would create a separate set of land layers such as hills, castles, far away trees, etc.

Then I would create multiple, independant foreground layers like tree clusters, bushes, flowers, waterfalls. These would be done sticker-style so that I could place them anywhere in the display that I desire.

The way I see it, given the items I collect, I would only have to do a few types of backgrounds:

* Fantasy Forest
* Clouds (either in day or night)
* Manly (for stuff like He-Man and Thundercats)
* Under Water
* Urban (for collections like Sweet Secrets, Fairy Winkles--it would be an indoor setting)
* Generic outdoors (like the picture above, but customizable for SSC, MLP, etc)

As far as the materials I would use, that is still undecided. I would want something really sturdy like particle board. I would have to paint the picture on sturdy canvas and glue the parts onto the board and use a jigsaw to cut it. I just want it to last. I think the materials question is probably my biggest hurdle in the whole project. Any thoughts are welcome on this. Meanwhile I will continue to search for props and dream up ideas.