Plus that the choice of aircraft is not the pivotal factor for A3 when it comes to this decision at this moment. Capacity considerations aside (which are of course important), establishing a new regular long-haul route involves high fixed and quasi-fixed costs, and is accompanied by significant amount of risk, especially if it is an airline's first one in a market. These factors are to a large extent invariant whether it is an A330, an A321XR,or a Cessna performing that route. As @
GUWonder wrote, better to maintain a functional regional airline in ATH than switch to a potentially defunct international one!