The track you run on looks spectacular. To do what you want, you will need a control unit track section and as many lane change sections as you can put in. I only have two singles at the moment, but plan to add two more. The going trend is to use the doubles more and the singles just where you need to pit in or park a pace car.
You can remote mount the electronics part of the CU, I did because my track is routed, and connect it to the track via wired connectors. I used a flat four trailer connector for the four power leads and then four smaller wires for the lap counter sensors. I also wired in my jumpers on the track side flat four connector. As you power it up in digital mode, the CU will tell you if you have any wires crossed, polarity is still important, just not lane priority.
When you go back to analog, unplug the CU to isolate it from back feed power and power up the analog side. There are some other mods you have to do to the start track and each lane change so the two lanes aren't powered by one controller. It's basically just taking the backs off an removing any jumper wires they have. You will have to re-arrange some jumper wires so you continuity on each rail in analog mode.
On SCI, there are many tracks run the way you want to run, some use a with box so it's a flip of a switch and others use a standard Carrera digital chip between the CU and the track so each isolated slot is chipped, not the car.
The standard CU supports four cars and theres an extension box that adds two more. I'm using those, but then all six drivers are too bunched up. I extended my driver stations out using phone wire, phone box male to male connectors and new plugs a plug crimper. I'm currently running a Pyle 25 amp, 15 volt power supply. I just bought a 10 amp, 30 volt power supply so my 1/24 cars have more zip. I used the Carrera plug and wired it to the power supply with a 7 amp inline fuse.