My solution would be to make it a hell of a lot harder to get a DL. Real testing, not ten questions and five minute drive. Using a tiered system would also be a good idea. In the mean time, pick a road for the stop and road for the right of way. If the speeds are to high that is a speed limit issue not a stop sign issue. If the traffic truly needs control then the intersection needs a light.
Roundabouts are great, the problem is the average driver is just to damn dumb to even grasp a simple single merge onto a straight road. Give them a merge into a curve and then a merge out and their tiny, tiny brain just locks up.