Being aware of one's limits and staying well inside the envelope.
Knowing a few airline pilots and listening to their experience of flying, it's clear that the airlines value discipline (ie follow procedures everytime), accuracy (why fly at 100 feet below altitude when you can fly bang on), awareness (are we on profile, where do we need to be in 5 mins etc, what configuration do we need/will we need ), safety (see disipline) and teamwork (CRM.) Handling skills to a certain level are clearly a pre-requisite!