As someone who learned to drive in Europe I've always been extremely confused by the signage and road layout of American roads. There is a pretty big difference in quality between state roads and federal roads. The former seem to have no coherent style, layout or identity while the latter seem pretty consistent. Given the above documents I can see there is a consistent style but the style does not seem to translate to a consistent user experience.
The three things that stand out to me are the amount of text on each sign, the lack of standardized rule about entries and exists, and the lack of road markings, specially at intersections.
The first one isn't necessarily a big problem but it's very weird to have all this text when you could have instead a very recognizable sign that you can understand from afar (the one way sign is a great example), instead of a white sign with black text that you can only read once you're close to it and only understand if you know English.
The second one makes highway layout extremely confusing and, at least for me, feel dangerous and stressful. Some Signs can tell you to take an exit with make 20m of notice and it's a 90° right turn and you also need to go from 120 kmph to 30 in that span. The reduced speed sign is only visible after you've turned so if you dont know the area you're almost always going too fast. Because it's a 90° turn with trees in the sides you can't anticipate what the traffic is like after the turn. If you know the area you probably have no problem handling this situation, but driving there for the first time feels like driving through a minefield. There are other instances of this with left exits, overtaking from both sides, turn right on red, stop sights everywhere, no priority system, and more.
The last one is incredibly frustrating when you come from Europe because over there, most intersections have redundant signage and markings. Intersections have street lights that tell you where to go, the road layout is advertised on a sign well in advance, and the paint on the road tells you how to turn and where to stop and even indicates speed limits or directions. Intersections in americas provide no such affordances. Intersections are basically a free for all between the incoming trafic, the people turning right on red and the pedestrians. I was expecting a lot more from a country which is built for cars.
It feels like roads are built for cars but not for drivers.