I think consideration should be given to turning off the signals at the northern end of Cornmarket and having that junction operate like the Holywell junction at the other end of Broad St.
I walk and cycle through this junction regularly, and there's pretty much always:
- a stream of pedestrians crossing on red across George St, as in the photo above - if they didn't they'd pile up and block the footways;
- pedestrians crossing haphazardly across the unsignalled Magdalen St West and Broad St arms, sometimes getting caught out mid-crossing by signal changes;
- mopeds and cycles going through red lights or using the wrong side of the road to turn from Broad St into Magdalen St West; and
- significant periods when buses and taxis and cycles are waiting even though the junction is clear.
Given the current poor compliance of pedestrians with signals - and the absence of signals for them on two arms - I think this junction would be both easier to understand and safer if it were more obviously and officially shared space, especially if it could be marked as pedestrian priority (with a surface layout like the Holywell-Broad junction, when funding permits, but perhaps with pedestrian priority signs in the interim) . As well as reducing pedestrian delays and/or stress, and delays to buses and taxis and cycles, reducing queues at this junction would also alleviate problems at the adjacent Broad St-Magdalen East junction.
I haven't done counts, but this junction has less motor traffic than the Holywell one - albeit more buses - and similar numbers of cycles, but more pedestrians. That suggests it should work even better as "shared space". The combination of constrained space and dense pedestrians seems to slow vehicles quite effectively, and the one concern with speed is probably from mopeds (which will largely disappear once camera enforcement of the central "no motor vehicle" restrictions goes in, except for the unregistered mopeds masquerading as e-bikes). There could also be a risk that peak pedestrian flows would be so high as to inhibit bus movements completely, but that seems unlikely. Bus drivers could be asked to cross the junction at low speed, as on Queen St.
(I realise that this area needs a full redesign, and that once the traffic-filters are in place there may be options to reroute buses, allowing more radical changes. This would be a cheap, fast interim measure.)
This shows a "Pedestrian Priority - Max 15mph" sign (advisory only) from the City of London; some of the junctions there would have similar traffic mixes to this one.
An alternative would be to keep the lights, but have them stay on red for motor traffic and "green scramble" for pedestrians and cycles until a bus or taxi arrives, when they would switch.