Like in that famous idiom, you can lead a horse to radioactive pellets, but you can’t make it eat.

There are a lot of ‘mini’ roundabouts in my country that are fully flat to the ground. The point is to set the rules for right of way, entering and exiting, indication etc in a way people find familiar (we have lots of roundabouts). Just one roundabout sign at each entrance with standard road markings and everyone knows what’s up.