As someone else pointed out, the Autobahn doesn't ever go through towns or villages. However, I agree that the frequent drastic speed limit changes on the Bundesstraße are a pain. I am not sure however what a good solution would be. You could lower the speed limit between towns, raise it the towns or build out the road in the city more and keep the limit higher like happens on the 101 when you go through some towns in the central valley. But that has other huge downsides, like being painfully slow or increasing the risks or ruining the towns. Having a town every 1-2 miles might just result in this.