Welcome to the forum! I'm also a new guy here.
The techniques you used for N scale will work just as well for any other scale.
As noted in some of the previous replies DCC will sidestep the wiring issues entirely. It might be a bit of overkill for a ceiling layout because you're probably not going to do a lot of switching although it does have some other benefits such as controlling lights and sounds and programming accel and decel rates.
I assume that you would want to control your turnouts remotely if they are near the ceiling. If you would like to use analog the simplest way would be to use a DPDT switch for each siding. One pole of the switch would control the turnout position. If you're using half wave AC switch motors (ex. LGB) wire a normally open momentary contact push button into the AC power supply to the switch motors them split this into two circuits using diodes to feed positive and negative half wave AC to the two outer terminals of the DPDT switches. The centre terminal will be connected to one terminal on the switch motor and the other is connected to a common ground.
The other pole of the DPDT switches would control the power (ON/OFF) to the siding. Each siding would have to be electrically isolated but you should already be familiar with this from your previous modelling.
Pressing the momentary contact pushbutton will switch all turnouts in the direction set by the DPDT switches and will shut off the power to the routes that have not been selected. I used this technique in my previous garden railway and it worked great. One advantage is that you can easily tell which route has been set by looking at the DPDT switches.
There's probably a hundred other ways of doing this so don't hesitate to just dive in and try your own technique. Good luck!
If you're going to be using DCC (or similar) command control, then power-routing switches aren't necessary. Since those systems address each locomotive individually, and the track always has full power, you want power going to both sides of the switch. Fortunately, most commercial switches in this scale work that way, so all you need to do is put some kind of DCC-compatible switch machine or other remote throw on them.
If you are going to use traditional track power, then the automation systems that you mention would work equally well in this instance. There are companies that make circuits to make that fairly simple, too, so you probably wouldn't have to wire it yourself if you didn't want to. Take a look in GR. Off the top of my head, G-Scale Graphics offers some automation control circuits, but there are others that I'm just not remembering right now.
Later,
K
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