Oncoming unprotected lefts are the most dangerous feature of city streets, and good motorcyclists learn to be extremely wary of their users.
Re: stopping in front of you - this is one reason why lanesplitting can actually be safer. If a car in front of you does an emergency braking maneuver, you're not pointed at the back of them. Additionally, you're not in the way of the car behind you who was watching Harry Potter on his phone and hasn't yet noticed what's happened. We call the longitudinal gap between cars the "squish zone."
You can reduce the danger of rear impacts on the highway, again, by lane splitting at a bit over the prevailing speed of traffic. At stops, you shelter next to, and between, larger vehicles.