Air France, British Airways, EasyJet and Lufthansa join the Irish budget carrier on O'Leary's shortlist.
He reckons Ryanair still has a long way to go toward reaching its full potential in Europe, and is casting his eye further afield: long-haul low-cost services to the USA are a possibility, he says, but only if Europe and America sign a full open-skies deal.
As it strives to maximise European business, Ryanair is exploring the potential of adding new bases to the 57 it already operates across the continent, with a focus on airports larger than the "secondary or tertiary" ones it already serves, and O'Leary confirms that German airports Cologne andDortmund have approached his airline with incentives to operate there as services by Air Berlin are cut back.
Network contraction by rivals is also creating opportunities in Spain and Italy, says O'Leary, while even busy airports such as London Gatwick - to which Ryanair operates, but at which it does not have a base - have slots at certain times of day amenable to non-time-sensitive flights serving holiday destinations.
As to the possibility of adding transatlantic services, O'Leary sketches out a vision of operating 30-40 long-range twinjets of the Airbus A330's or Boeing 787's size, but notes an obstacle: lack of aircraft availability due to the order backlog created by Gulf airlines' expansion.
In the nearer term, Ryanair is planning to revamp its website. O'Leary describes the current interface as "too clunky". Buoyed by the success of its reserved seating initiative, the carrier is planning to expand the number of rows allocated to the system, and O'Leary is looking for other service innovations to join priority boarding and luggage charges among innovations that have changed attitudes toward low-cost short-haul travel.
The Ryanair chief says that as a result of its introduction of charges for checked-in luggage, only 19% of passengers now want to check luggage in. He sees a future in which airports are transformed because they no longer need check-in halls, baggage-handling systems and lost baggage recovery systems, and in which passengers will be able to arrive much closer to departure times.
Airports will hate it, he says, because passenger dwell-times in the retail areas will reduce, but airport buildings could be much smaller and simpler.
Meanwhile, it looks as if Ryanair's existing baggage plans will soon be modified to introduce charges for putting large carry-on bags in the overhead racks being charged. Only those that can fit under the seat will be free.