Hybrid Between Wait & Quick Stop#5077

Currently, there are 2 stops: wait and quick. The wait stop forces a train to wait until the train is completely finished loading/unloading. The quick stop only keeps the train stopped when it’s actively loading/unloading. I believe a third stop type is desperately needed.
The type of stop I want to propose is a hybrid between the two. It would act like a quick stop, but wait until ONE car is full/empty after the initial load/unload. This would fill a huge gap in train functionality, as trains currently will often group up even with the perfect usage of wait/quick stops. Especially on the unloading side, using wait stops results in factories being starved of resources in some situations. This stop would solve those issues.
For example, using a wait stop to unload circles and squares to a factory that stacks them will back up if the the train delivers a shipment of squares but not circles. A third stop would fix this: one that acts like a quick stop but will keep waiting as long as no efficiency is lost. The train would unload the squares and immediately leave as it has no circles to unload.

The best approach imo would be a configurable station logic kind of like what Factorio does. Interface should ideally be through a button for the station so people who don’t want to mess with it can just use the default modes.

the team have said that they want to keep dropdowns and settings for buildings to a minimum. there’s already a stop category in the toolbar, so i don’t see an issue just adding a 3rd stop. in the future, if a wire controlled stop is added, that could go there too

I want a version of the Immediate Stop that, on stopping, determines what it can do in a single action, does that one action, and moves on, REGARDLESS of it it could do another load/unload cycles by the time the first one finishes.

And they definitely need to fix the stupid “the train will start moving then stop again AT THE SAME STOP” bug.