One more idea on spacecraft but this one will be harder. Another one famous space fandom is StarCraft. There are a lot of beloved ships, big and small. Best of them is terran battlecrusier and here are also wraith and medivac. I've shown only some terran ships and there are also protoss (aliens) and zergs (biological beasts). Many would be glad to see some of them in SE but the initial in-game models can't be used in SE, they are pretty low-poly. So the talk is about some model remakes. I don't know where they can be found, it will take time to find good ones and get authors' permission.
Here is the page of 3d-artist who made the 2nd and 3rd ships:http://xiaorobear.deviantart.com
I didn't write him.