The good rule that most of Europe uses is that motorcycles can "lane filter" (i.e. go in between lanes but only for cars that are basically stopped and only at low speed). Going between lanes is suicidal at high speed, but if cars are <5mph and the motorcycle is ~10mph it's actually safer for the motorcycle because it removes the chance of them being rear-ended. (It also makes motorcycles faster than cars which is helpful for discouraging cars in cities)