A serene Japanese Garden for your minifigures to relax. Featuring lots of plant elements, a Japanese arch, Koi pond, fence, pebble path, bench, lamp, and a tree.
After seeing the spring polybag, an idea of bags of bricks filled with nature elements to make seasonal scenes came to mind. The concept would be to supply to bricks and instructions using techniques to create authentic looking natural scenes.
If this were to be made, it could be a stand alone for the Creator series (similar to the houses), or multiple seasons and natural locations could be made. I also see this as a good package for use at LEGO Store building sessions with kids.
Jay from theBrickShowtv meantioned that LEGO should do more of this: http://www.youtube.com/watch?v=wCPWB7wfA_Q&t=9m40s