The Canaries and Med holiday routes are well covered at EMA. It is often the best/cheapest Midlands/Yorkshire departure airport for flights to and from any of these type of destinations in or out of peak season.
The way I see it expanding now would be to try and attract more business from Eastern Europe. We have a few Polish options but Hungary, Slovakia, Czech Republic, Romania, Bulgaria and the Baltics all have routes that could work from here. Could Wizz venture up the M1?
Could FR add Tallinn, Bucharest, Podgorica, Plovdiv and fill the seats? I think maybe..