I am glad that Facebook’s team takes so much effort to get those roads mapped. A few minor glitches like unconnected roads may happen, and also here in Germany the map is far from perfect (and Germany is among the best mapped countries).
Well, perhaps my “use case” is different from other persons’ use cases: I travel on bicycle, normally away from major roads (I don’t like the noisy traffic). Often, those areas are not mapped at all. Seeing some “unconnected” roads on the map means that the way I am traveling on may perhaps lead to that way and does not end in nowhere before (perhaps somewhen later on…). And some “agglomerations” of minor roads may indicate that a village is nearby etc. Such information does help.
Could you perhaps improve your algorithm to differentiate between paved (apshalt/concrete) and unpaved (dirt road, gravel, …) roads? Just imagine the rain starts during my bicycle tour.