Council Bluffs Sub Design - Revisited

I have been working on 3d printing projects for so long now, and decided it was time to refocus some attention on a new layout project.  As you may be aware, several months ago I created a design for a Union Pacific Council Bluffs Subdivision shelf layout, which would be built in 2 sections for a total of 16' in length.  I even had the beginnings of the benchwork for the two tables.  After some additional thought, I have decided to reduce the overall size of the layout, and change the shape into a long "L".  The main reason for this is the fact that my garage space where my layouts are built and displayed won't accommodate 16' without a car parked outside.  Secondly, the thought of having a seam between table sections just doesn't appeal to me.  So going back to my trusty 10' length, I came up with a 10' x 4' "L" shape shelf layout.  In order to make the plan work, I did add a removable extension.  Another feature that I thought would give this design some added interest is a set of staging tracks behind the long backdrop.  The tracks will be accessible to the front through a hole, hidden by the grain elevator structure.

I used MS Excel to create my last track plan, and since I have been using Sketchup to draw my 3d objects, I thought I would use it for my layout drawing as well.  I have only spent about an hour total on this drawing, so this is far from complete, but will give you an idea of what I am trying to achieve.  I don't plan to put a lot of detail into this plan, as I would rather spend the time building the benchwork and laying out the track configuration on the real thing.  With all that I have going on, I need to find ways to cut corners, without adding risk to the project.

The industries on this layout will be similar to what I designed in version 1, taking into consideration the truck/trailer combos that I want to feature.  Again, this is a sloppy first draft, but using 3d helps me visualize my ideas.  My goal as of now is to have enough of this layout finished to display at the Council Bluffs Great Train Expo in February 2014.  We'll see how far I get.  As always, your feedback is greatly appreciated.