It would be much safer to have cyclist priority on the slip roads here as is done in The Netherlands http://www.flickr.com/photos/smsm1/10046288016/ , or even the following example from Britain: http://www.cycling-embassy.org.uk/photos/good-cycling-facility-of-the-week/good-cycling-facility-of-the-week-14th-november-2013-0

The slip roads also need to be narrowed to slow motor vehicle speeds as does the turning radii of the roundabout.