The roundabout is not that hard to figure out. Probably the most important thing is to know which lane you need BEFORE you get to it. Doesn't take a genius to do this. It works fine as long as people are smart enough to figure it out.  And if you can't, then you certainly shouldn't be in possession of a drivers license. All the wrecks there are caused by idiots who cut across the lanes instead of following the lane they entered the roundabout on.

It's not the planning engineers' intelligence that's the issue, its the intelligence of the drivers.