A problem in all of Michigan, and compounded by the enormous population of Grand Rapids, is the lack of clarity identifying crosswalks
Different types of roads have different crossing rules, and those rules are far from clear and rarely made obvious by the signage on the roads. Sure there are subtle differences in signs, but only civil engineers can actually tell what's what. Pedestrians used to one type of road expect cars to stop at any and all intersections, but it's not legal for cars to stop on certain roads. This is hazardous when pedestrians walk out into unsuspecting traffic or when a well intentioned driver stops suddenly for pedestrians in an improper place. On the other hand, pedestrians used to crossing roads where cars can only stop at lights will confuse driver's in areas where cars are supposed to stop at any intersection creating delays.
I know I have definitely made mistakes both as a pedestrian and as a driver because of not knowing what sort of road I was on and which set of rules applied. This problem is magnified as a visitor to Grand Rapids from a small town.
Unfortunately this is probably more of a state problem than a city problem, but I think Grand Rapids would be a greatly benefit from improved crosswalk signs and road/pedestrian rule communication.
Similarly, it is not always obvious to biker/driver's where bikes are allowed or not. Are bikes pedestrians or vehicles? It seems to be a free for all. Signs and education are definitely needed.