Ryanair
Since they set up its BRS base in 2007 Ryanair has seen routes come and go with bewildering rapidity at times. This is a list of those the airline once tried (may not be a complete list) but doesn't any more, with routes now operated by other airlines marked with an asterisk:
Derry, Dinard, Gdansk*, Grenoble*, Katowice*, Salzburg*, Scezecin, Shannon, Cagliari, Eindhoven, Pau, Perpignan, Montpellier, Toulon, Trieste, Bydgoszcz, Bratislava, Rimini, Porto*, Belfast City, Marrakech*, Seville, Riga and Lodz.
Summer 2015 should see 28 routes according to Kenny Jacobs but Reus appears to be not available for booking which would leave 27.
As for Gran Canaria, Ryanair operates once per week in winter, twice a week in summer.
The point I was trying to make was that if Ryanair ever did assume easyJet's mantle of biggest airline at BRS it would not be a case of expanding a bit here and there but one of substantial route development.
That's why I'm sceptical although no timescale is given so it could be something that might occur gradually over the next decade or longer. Certainly the BRS management thinks that 10 mppa and more overall pax figures are achievable in the future - it's currently at 6.3 mppa with anticipated growth of 6-8% this year and expecting to go through 7 mppa in 2016 according to the airport's aviation director - and the passengers would have to come from somewhere and have services to use.