In that video you posted, on the standard roundabouts, it seems they have most vehicles entering the roundabout, and taking the first right exit. I am not sure that is realistic. If you have most vehicles taking the second right exit - going straight thru - or even the third exit, it would make the traffic flow look much different.

On some of the other designs,  they look so complex to be confusing. I am certain if people are driving those designs daily, they would get used to them. However, for the driver that is new to an area, and encountering one of those more complex designs......  I can envision a driver stopping in mid-traffic, completely confused which way to go.  Ugh!