Already discussed elsewhere:
[Kovarex] [0.16.5][Mac] Fluid Wagon Gui Bug
Version 0.16.7
Friday Facts #222 - Christmas avalanche

It seems to be a bit more common in the new map generator. Either crank up the amount of water or reroll your map a couple of times.

Adding some thought to why the fluid wagon wasn't intuitive to have it configurable: In a 2-1 or 1-2 configuration the wagon isn't symmetrical Symmetry is only a (small?) issue if you use single track rails with bidirectional trains. My trains only go forward, there is only one orientation. The mai...

Check the Angel and Bobs mod packs. They do stuff like this.

I always viewed the separate tanks in the fluid wagons as a logical equivalent of item filters in cargo wagons. It provides a simple way to do more with a single wagon and thus a more flexible solution for the smaller scale. The fact that this could be done was a bit surprising at first, but great a...

Blue science really is the point in the game where you need to take automation serious. You can play around with red and green but no longer with blue. Roughly you need to take the following steps for the science packs: Red : Copper & Ore smelting Green : Green Circuits & Automation 2 Milita...

So essentially it would be a chest, an unloader and a circuit condition. Sounds like an idea for a mod, but I don't think it really adds to vanilla. I think it is a good idea to give the community some time to adapt to the loss of compression tricks before rushing out all kinds of specific solutions...

I see little reason why not to do this. It is consistent with behaviour in vehicles and does not break anything. If anything it makes burner inserters more viable in the late game.

Yes, I was thinking the same. It is very easy to accidentally wipe your setup now.

I was thinking that belts should maybe not replace splitters and undergrounds while splitters and undergrounds would replace belts.
Replacing them only based on direction is an interesting idea.

I am not sure what problem this would solve. Underground belts can already easily transport "up" or "down" a cliff. Cliffs do not really exist in the game, i.e. there is no actual height implemented. These are just walls that create the illusion of a cliff.

Or they could just fix the graphics such that it isn't so hard to see.

A slight variation on the almost stereotypical early game build aimed at simplicity.