I am not sure what is possible to do, but it still bugs me that the game treats stop-lights like stop-signs for opposing lanes, instead of acting like real stop-lights. The obvious issue is as stated. Intersections become a head-on free-for-all at intersections. People try to turn left, across oncoming traffic and run across pedestrians in the process.

How real lights work... With cross-walks...

1: Lanes "Full stop", pedestrians cross, intersecting lanes stop or yield (all-stop intersection option), right-hand turn yields to all
2: Crosswalk stops, Left-hand ONLY turns on signal (if left-hand signal exists), right-hand turn yields (should have no opposition to turn)
3: Crosswalk stopped still, Forward light, left-hand yields to all, right-hand turns freely
4: (Optional "all-stop intersection" period), then "Trigger opposing intersection cycle" and wait to be triggered by opposing intersection trigger.

For intersections that do not have "left-hand signals", the left-hand traffic would just "yield" to all oncoming traffic. Which the game does horribly... It yields way too long, then drivees head-on into traffic, prematurely, after waiting too long. There is normally plenty of room to enter or cross, way before the vehicles start to actually move. I think they have the timing reversed for head-on yield VS in-line (flowing) yields. (The yield when entering round-abouts, is horribly LONG, waiting for a clearing of 3-4 car-lengths before attempting to enter. Normally, people jump right in, at the first available clearing! Yet, they still crash and impede traffic in the process! Again, I think the developers may have adjusted the wrong "delays" for yields, for the two types of yielding. Crossing vs in-line yields)

Anyways, this change would make street-lights actually become functional, instead of a failed mess of traffic control. It would also probably fix yielding issues, if the later changes were adjusted too.