Better Media Unit resolution, graphics and UI. Its functional but pretty average really.
Extended interior ambient LED lighting
Better dials more in line with Audi (though seems they will be a dying item due to virtual cockpits, maybe standard on the MK

More wheel choices at lesser uplift cost - trading in the existing wheels and then adding nearly £1000 is extortionate
Being able to select modes by just pressing button to activate and then to keep pressing button to move through menu before timing out
Losing that silly little window in the design (its really picking at the small things now!)
DCC as standard
To be honest its just a great car of the size that personally seek, and with the options available (which maybe would like as standard) and now with Car Play there is very little to change aside from the usual uplifts in engines (greater economy from the R) and maybe additional gearing within the DSG thats been mentioned recently in articles seen.