Sydney has a crazy number of signs but I like their use of yield signs and relative lack of unsigned intersections.

It took me a while to learn to automatically look for European yield signs. It was by far the highest effort to change between the two systems for me.

I don't like the default to yield to progress as it means one is looking for the absence of something most of the time.

You always have the right of way in the U.S. unless there is a stop sign or a yield sign. If both directions have stop signs, then the person who arrived first has the right-of-way. To me, it's more straight forward to always have right-of-way, but that's probably because I'm used to it.

Unsigned intersections exist and they work as in Europe. The reality of them is people handle them relatively well as long as lines of sight are good, and when they become a problem they’re improved (usually by adding a stop sign that people ignore).

Traffic calming is better done with mechanisms not signs.

I only really see here stop signs when there is either very poor visibility or very high speed difference. In my mind it works well enough.

> You always have the right of way in the U.S. unless there is a stop sign or a yield sign.

Incorrect. There are explicit right of way rules for completely unsigned intersections. Yes, they do exist. My neighborhood hasn’t been fully polluted with stop signs yet, so about half our intersections are unsigned. The last crash in the neighborhood that I am aware of was about 10 years ago and was wholly unrelated to intersection control.

Driveways, parking lots, and some merge lanes don't have stop or yield signs. So it's not always marked.

Much more interesting are one lane tunnels or bridges that have a yield sign on both sides. Effectively, people just do fist come first served, but if it's at the same time you have to negotiate who has the right of way.