I have just been learning the game's circuit system (yeah, after years!) and hooking up a gate system with my rail network which will display lights with one of 3 colours; green if the train is at the station, yellow (wish it could be orange) if the train's about to leave and red when it leaves. This also locks the gates when the lights are red.
As I'm working on this, I realised that I don't like the way that wires droop across a rail when you hook up devices on either side. Some ideas I had about how this could be made to look less like a train will just rip through the cables are;
Ability to connect wires (green/red) to either side of a rail, having the wire shown going across the gravel under the rail when connections are on both sides
-OR-
When cables are placed going over a rail, have them get their own overhead conduit track that would go over the train.
(edit) Another thing I just noticed is that when you place a gate on a rail and connect it with a wire (well, the adjacent wall block), the "Read sensor" checkbox underneath "Mode of operation" mentions that it sens a signal when a player is wanting to open the gate. I think on gates that are placed on rails there ought to be another checkbox that does the same but for trains. This would be useful because I wanted to use gates to stop a player being able to walk down the track, so those would receive a constant signal telling them to remain closed, however this currently doesn't respect trains and so they just demolish the gates.
I know the devs are working hard on polishing the game up a little before the 1.0 release, and as someone who notices little nuances like this all the time, I would highly appreciate if such things could be added to the game
