Focusing on development is not a panacea--I see plenty of places that are trying to 'develop' but it is just sprawl. Plenty of places give huge incentives and pays for road upgrades for things like corporate parks that never fill up or pay for the investment. Roundabout also have the effect of not needing expensive traffic lights and not needing as wide of roads. They increase throughput and thus can decrease backups. If you only have 2 lanes instead of 4 it is much less expensive to maintain.