Still armchairing around and thinking about it all. I am in a quandary. For the lower deck, do I go down the path of a dogbone idea or go the single track with ballon loops at each end?
The dogbone has the benefits of looking like a big mainline, but then you get a guaranteed 2 tracks everywhere. This makes design a tad harder.
Some industry will have to come off the up line and others off the down line - no biggy, but has to be catered for.
By only having a single track, then it's a no brainer to either put a left turnout in to go to an industry on the left or a right one to turn right - no second line to worry about. This single track design also then gives the option that some scenery can be done so the line looks like a branchline in places.
The single track would definitely make operations more interesting, there is that.
Of course both designs would get plenty of passing loops, the single track in particular!
Oh well, back to reading design books and jotting down ideas and thoughts and the occasional drivel. (shut up Craig, I don't carry a drool bucket strapped to my chin!)