Ideas for 'L' shaped layout

[btkrausen]

Looking for some ideas on my new 4x6x2 layout (it's two 2x4 boards as an L) for N scale. I've been going through random images online and looking for ideas on the layout but still struggling to figure something out. Ultimately, I want to be able to run two trains simultaneously but don't really want to run just two tracks parallel throughout the layout. I do have a 6-inch backdrop so I was thinking about some false-front buildings for an industrial look on one side. Likely do a mountain/tunnel in the back corner but I'd love to have something that's multi-level.

Any thoughts?

A few pics of what I started on when I only had the 2x4 and decided to add the second 2x4 board below.

[Hansel]

Here is a link to my blog where I documented my build of my "L" shaped layout.  I have been working on it for the last 15 years or so, with many changes along the way.

https://thecentralpennsylvaniarailroad.blogspot.com/2017/04/here-is-where-it-all-began-back-in-2009.html

I also added as an attachment another revision to the layout.