This photograph shows the roundabout at Potters Bank in the snow. The absurdly-small pedestrian refuge at the foot of Potters Bank is in the foreground. You can see from the snow cover that there are vast areas of the road which are not actually required by vehicles and which only serve to increase speeds through the junction. Junctions are exactly where speeds should be reduced, not increased, as it smooths traffic flow, increases junction capacity and reduces danger.
The approaches need to be narrowed, to ensure that only one car at a time can enter the roundabout from each direction, making it safer for vulnerable road users. The pedestrian refuges need increasing in size. More radically, the whole roundabout could be removed: this is only a T-junction after all, with the space saved being dedicated to segregated cycle lanes stretching from Prebends Bridge up Potters Bank and along Quarryheads Lane to the university.