Everyone's contribution is great! I do want to make special comment to RickO and Paul 2.
Rick, I like the winter snowy area you have along with a summer area. I think it works good.
Paul, I have noticed your second shelf before in photos. I think it and the transition areas work.
I have been thinking for about a year or combining the two ideas on my layout I hope to start this winter. I would have two levels, both on shelves like Paul. The upper shelf would have a winter area where I could put some of my wife's porcelain and ceramic buildings on display year round. The lower level would all be summer with scale buildings and one area of a few operating accessories. I'll see how I can cram that into an 11 x 11 room.
Your contributions enables me to better visualize that. I think that was the kind of thing Alan was hoping for when he started this topic.
Thank you, all!!