BA had all ready bought out City Flyer by the time they chose to axe Cork. Cork was axed because of corporate greed by British Airways managers. Cork was profitable but BA wanted more so they decided to use the aeroplane to try somewhere else.
City Flyer used ATR-42s, ATR-72s and BAe RJs from Gatwick so a full spectrum of different sizes there. Something the size of a ATR-72 or bigger would probably be best for LGW all right.
As for EI Cork is just an irritation. The closest EI has come to creativity in Cork is to axe Dublin leaving all the fat to RE and to cut LHR for the coming summer, cut Paris and cut Amsterdam to provide 2x7 services to BCN, ALC, Milan. What geniuses!
Yes, I just want to add my support for the great service we had to Nice - five times weekly last summer to zero this year. Great loads too. Such a shame!