How can roads be "just right" when they fail so frequently? i think complaints of micromanagement are oft-times misplaced. This is a management genre afterall. It is one thing to have dozens of busy works to do each turn. It's quite a different thing to have adequate decision and control. i think roads can be done proper with less micro-management than some people fear. 

For myself, keeping in mind some player aversion to worker units, i'd compromise for progressively built roads (not instant) for which the path of the road is laid out by the player. And be able to build roads upon whim.. but for cost. i ought be able to build a road dead-ending to a dangerous forest if i wish. At this point roads have limited tactical purpose with about zero player influence. i think this is bad.

While I agree that manuall road building is a pain right now (the toggle idea would end that) I definatly prefer my own roads to instant ines.

The worst thing about the instant roads is when at turn 35-40 (epic) 6/8 capitals are allready connected by one AI that power researched roads. Within 3-4 turns (without horses or a stable network) everyone can reach you so that questing/hunting 5-10 tiles off-road with my sov is allready an invitation to declare war on me.