Switching layout

A harbor railroad might meet your needs.  They are basically a switching layout.  The addition of a car float adds interest to the layout and functions as a fiddle yard to add and remove cars from the layout.

Here's one that I designed several years ago.  It's 10' x 10' x 10' but could be shortened to less than 20'.  I've incorporated a Timesaver at one end.

Jan

Switching leads will be a problem. The train room for the Plywood Empire Route is 12'8" X 11'6". I managed to fit two industrial switching areas by wrapping around two corners.

The East End:

The West End:

Looking South with the East End at left and the West End at right:

Here's the thing: to switch the Paint Factory the main line along the West wall must be used as a switch lead:

Wrapping a single track lead at either end of your 16' would be very helpful.

BTW, an operating session on the PER requires 30-50 minutes (depending on incoming consist and what cars need picked up) to do all the switching work. Just 5 track switches. 

Very nice layout Lew!  Model railroading is fun in any space.  Switching pikes have always held a place in my heart, they remind me of all the "real" railroad stuff I see.  Sure it is fun to watch passing trains with mile long consists but when one rail fans the prototype, he has to wait a long time between trains but if one goes to the switching districts, he is amused at times for hours and sees exactly what you are recreating in miniature.  I love how you incorporated some operating accessories into the mix for even more fun! 😊

A run around loop like Lew has will add some interest if you want to occasionally sit back and watch a train run.

You might want to check out the thread on the Gum, Stump and Showshoe switching layout. It could easily be stretched to 16 feet. I think the build could be quite satisfying.