Time for me to comment. My experience relates only to that from Thorpe to the Wroxham Road and for someone that is pretty used to some pretty nasty roundabouts in Hertfordshire and north London, I find the roundabout at the Wroxham Road horrible!
Ways to improve would be to give those going left a dedicated detached lane continuing into its own lane rather than needing to filter in/give way when joining the distributor road / Wroxham Road. (does that make sense). They have done it at other junctions so why not here.
Because the roundabout is so wide, many vehicles are able to come round at the same time and since they rarely indicate, you end up waiting far longer than is needed just to be safe. Alternatively, you take a risk...............
Lets hope something is done and soon!
Liz