One way to address these complaints is by providing proper infrastructure. Quite frankly, when on the road you have to behave like a motorist. Sometimes your observations are a matter of perception. Consider a light turning amber, a cyclists still has to go even though the light is timed for motor vehicles and will be red by the time they exit the intersection, because the car behind you will will go because the light is timed for motorists and will not turn red by the time they exit the intersection. Sometimes it is a matter of safety, because there is a good chance the car behind you will enter the intersection as the light is turning red. As for people entering the intersection after the light turns red, I see this far more often with motor vehicles. By far more often, I mean I have seen cyclists do it as many times in a decade as I have seen motorists do it in a day.
While signalling would likely be helped by education, it is also worth noting that it can be difficult for cyclists to do it at speed on a busy road. Remember, they are on the road because the infrastructure does not exist and they are at speed because they have to keep pace with motor vehicles (within reason). Again, proper infrastructure would help. That includes bike lanes that are free of debris and where the surface is properly maintained. Ironically, hand signals are only systematically taught in driver education (some cyclists don't have a drivers license), few motorists seem to know what they are, and not using the vehicle's turn signal is common among motorists.
As for not stopping for pedestrians, that is common with both motorists and cyclists yet it creates more problems for cyclists. Simply put, when there is less than a one in ten chance that the car behind you will stop for a pedestrian it is very risky for cyclists to stop for pedestrians. Again, this is because a lack of proper infrastructure means that cars and cyclists are mixing.
An often forgotten aspect of cycling is that it takes significant energy to slow/stop and then speed up again. Traffic lights are often designed purely to stop motor traffic from colliding and very rarely take the needs of cyclists into account. A cycle lane that cedes priority at every side road is going to be next to useless for competent bike commuters and similarly, multiple sets of traffic lights will often be ignored by cyclists if they know the junction and can see that it is safe for them to proceed. Indeed, some places allow cyclists to treat red lights as "proceed with caution if safe to do so".
The most important thing to realise is that cyclists pose very little danger to others and will often come off worse in a simple collision with a pedestrian, whereas people in cars are shielded from collisions whilst also posing a much greater danger to others.
While signalling would likely be helped by education, it is also worth noting that it can be difficult for cyclists to do it at speed on a busy road. Remember, they are on the road because the infrastructure does not exist and they are at speed because they have to keep pace with motor vehicles (within reason). Again, proper infrastructure would help. That includes bike lanes that are free of debris and where the surface is properly maintained. Ironically, hand signals are only systematically taught in driver education (some cyclists don't have a drivers license), few motorists seem to know what they are, and not using the vehicle's turn signal is common among motorists.
As for not stopping for pedestrians, that is common with both motorists and cyclists yet it creates more problems for cyclists. Simply put, when there is less than a one in ten chance that the car behind you will stop for a pedestrian it is very risky for cyclists to stop for pedestrians. Again, this is because a lack of proper infrastructure means that cars and cyclists are mixing.