I don’t see the problem with marking missing / incomplete streets etc in Openstreetbugs. I’ve done it a few times myself. Its useful if I notice something is missing, but I’m not able to survey it properly then, so I have a reminder to return and map it. Or another mapper in the area can fix it.

Though I suppose it might be useful to have different categories of bugs. Then you could choose to only display “missing street” bugs, or wrong name bugs, or whatever type you want to see.