Lessons I learned from my 2nd layout

Unfortunately my layout needed to be dismantled to permit 3 foot access to the electrical
panel (solar panel installation).  Back when I was active on the forum (4 K posts within 4 years) I used the knowledge I gained to permit me to run 35 + trains  (with more than 50 engines) on 13 loops simultaneously.  It was a glorious ride and very enjoyable (4engine MU’s – Rdg and UP, Double and Triple headers – C&O and Rdg).  Almost everything has been boxed and I have discovered I have more than 60 engines and far more cars than I can ever run in my much scaled down layout rebuild even in two houses. 

I have learned a couple of lessons that I would like to pass on:

1. Assure that you have adequately sized popup holes to access every point on the layout.
2. Steel threaded risers do work and permit closer placement of track than traditional wooden risers and ease of adjustment.
3. While space between levels can be as low as your Pantographs’  height, access to a derailment inside a triple main tunnel on the inside track can be difficult unless it is higher.
4. Avoid curved turnouts where possible. Side rods caused a short on my O54 turnout as well as pilot issues on some of larger engines stressing the necessity of very level transitions between supports on higher levels.
5. Do not put a bridge on the exit of a curve. Allow a transition straight section before the bridge.
6. The Acela showed me that if I wanted a straight section between curved sections of track have at least one car length of straight section before continuing or changing the curve direction.
7. While is nice to purchase items before you build the layout consider the geometry of the items being purchased and limitations it might place on your layout if you use it.  Examples I purchased are the Kline 3 bay coal unloading ramp (too long and straight) and the Bowser Turntable (too much space)
8. If you are looper as I am, do you really need all those turnouts? 
9. Speaking of turnouts, try to avoid back to back turnouts because some engines will stall at speeds less than 20-30 smph. (Alco S2’s and P5a’s).
10. Wire operating accessories before you build the level above that accessories (do not forget turnouts).
11. Watch where lighting fixtures are located. As the layout grew, my arms must have gotten shorter and light bulb changes became an adventure (purchase of remover on a long handle helped).
12. To permit more operating loops, my 2^nd layout avoided ramps between levels.  I have not been successful on this area; however, this time any transitions will have on engine length before starting and ending an incline.
13. Purchase train products based on features and not on vendor.  Both TMCC / Legacy and Proto2 operate well together.  Do not worry about obsolesce.  Kline went out of business and I have inserted Proto 2 into 4 Kline engines (including a slave in an AA F3).  Also conventional engines such as SMR can be out fitted with either ERR (TMCC) or Proto2.