LGS - I agree EU labour mobility will expand the market. Howevere 5 carriers competing and needing to make a profit suggests a vicious battle for consumers. The only EU routes I can think of from the UK where 5 carriers survive typically have 12 or more flights per day - routes like London to Rome, Alicante, Palma or Malaga.
Maybe Easyjet will make money on the route but I just don't see room for 5 profitable players - best guess is that 1 airline will end up being squeezed out after a price war.