With the proposed extended wrap around pedestrian island in the way,
the buses/fire engines from Dartmouth Rd might have trouble negotiating the corner, if they wanted to go (what is now) straight on.

I tried with a scaled bus shaped rectangle cut from a quorn burger packet on google maps, so I think I know what I'm talking about.
It would not be a comfortable manoeuvre, especially in front of the 'launderette' corner with a crowd of people waiting to cross. And those on the island would not be expecting a bus coming up behind them.

Maybe it sounds worse than I imagine.