I really do NOT understand the point of arguing about our supposedly being in a better position (possibly) if we did NOT have roads. That makes very little sense (even if it were true). Currently we have roads, and that is our starting point.. NOT some hypothetical fantasy land world without roads, and that life without roads may be more of a Richy_T argument rather than attributable to other libertarians.
Again, you miss the point. It is not about the roads directly, it is about government control of the roads. Now, you will say that the government has to be in control of the roads and that, indeed, is the point of contention. That centralized control reduces the opportunity for a wider range of solutions.
Yes, roads seem to be a very good example of a public good, and if roads are a public good, then the public has a right to have input into their direction, extent, quality and quantity... amongst other things related to such, in the event that they are considered to be public.
As we know, sometimes roads can be private too.. as I would presume most of us recognize there are still concepts of private property rights that are recognized that will end up involving private roads built on the private property.
Having public input will likely result in varying degrees of control, and sometimes, these control may be given up - depending upon the extent to which public interests are perceived to be a factor.