Suicide Junction LOOKS very complex, the sort of thing you see at yard or major station throats. I think it's very clever because trains can either continue on around the layout, or reverse direction, all without polarity issues and in a very compact area. To do the same with Marklin track you'd have to do a lot of kitbashing because they are "power everywhere" (MTL don't make crossings).
Lights: Both Marklin and Viessmann make German-style colour light signals in Z scale, and I believe that you can get US-style searchlight signals.
Track power: There are four approaches to the junction and each one of those could be controlled by an isolated section of track with it's own feeder that could be switched on or off. All of Rokuhan's 110mm straight sections take a feeder and they also make isolating track joiners.
Switching logic: I suppose it could be done with analogue gear, but would there be scope for using a DCC controller? Expensive yes, but maybe easier.
Detection: I'm not at all keen on the idea of affixing little magnets to the underside of locos. Viessmann make a track block occupancy detector, which might do the job, or maybe Rokuhan will come up with an equivalent to the Marklin circuit tracks.
"Never let the prototype get in the way of a good layout".