The chance of collision should also be considered. Since intersection collisions are the same or worse for riding a bicycle on the sidewalk, we should consider

The chance of collision should also be considered. Since intersection collisions are the same or worse for riding a bicycle on the sidewalk, we should consider overtaking while there is insufficient space which seems like it would be a strong function of extra space on either the road or the sidewalk and relative speeds. Im not sure why you listed 60 as I'm not really aware of any roads with such a limit that also reasonably expect bicycle traffic.