[dirtyroboto]

On point 5. Roads.

I guess the OP being from America plays a big part in their views on driving in Japan.
Having come from London I can say that even driving through central Tokyo is a pleasure for me.
At least in Japan, the road system can be used for it's intended purpose. In the UK it can be a fruitless exercise just driving 500 meters.

Onto Dislikes...
[Generalisation]
The Japanese have no spacial awareness. When they are walking, driving, cycling ect. they do not pay attention to their surroundings, and have poor control over their choice of locomotion.
When they have to make a split second decision it is mostly the wrong one.