Expect a statement of facts from Lothian Buses or Transport for Edinburgh? As best practice and parallels the way rail and air incidents are reported.
Bus was coming in from Barnton? Which route?
From the position of the bus (presumably the one involved in the crash) the driver has stopped pretty smartly after the collision and would have been travelling at a speed appropriate to stopping at the give-way line if required. We will learn more in due course but the delivery of a statement of facts will stem any wilder speculation. (bus route, bus speed, distance to stop beyond point of impact, point of impact)
Most serious bus-pedestrian collisions involve the victim going down and under the front on the nearside, and then passing under one or all 9T (maximum) axles. To consider perhaps having stiff nylon brushes positioned (and angled outwards) just in front of the front wheels, so that these can be set as close as possible to the road surface (and possibly the same at the rear). The brushes would be mounted on an airbag do that they would 'retract' as the suspension is lowered to assist boarding, and extend when the suspension is raised (ferry lift) to enhance ground clearance
This mini roundabout has corner radii that invite speeds higher then 30mph let alone 20mph. The swept area for all normally permitted vehicles is a doughnut with a centre radius of 5.5m and outer radius of 12m so that this junction should be reviewed to deliver the generally recommended corner radii of 6 metres, which should ensure that:
1) speeds through the junction are kept down
2) crossing points are placed to be 'visible' and width of the crossings pulled down to single lane.