I'd love to know what the list of cars are that you've driven where 60HP was the ceiling. About the only car on sale these days that's down in those ranges might be a used smart -- I think even all of the new ones make at least 70hp (52kw). Even the Ka I think bottomed out at 70hp and every time I saw one of those on the autobahn drivers seemed to spend more time trying not to collide with it than it did maintaining any kind of decent speed.
I can attest to having driven several cars at several HP ratings on the autobahn and felt terrified in cars that spent 13-15 seconds getting up to 100kph let alone the kinds of speeds most of the traffic was going. It wasn't until I picked up an Audi A3 that felt even remotely safe in day-to-day autobahn driving. At least Germans tend to drive better than Americans on those kinds of roads and do a good job of maintaining the appropriate lane for traffic going their speed. But still, top end of 60HP on the autobahn? shudder
edit: For reference, here's a 60HP Peugeot with the engine absolutely pegged on the Autobahn doing about 160kph (about 100mph) and getting passed like it's standing still a couple of times.