penguina my friend, obviously if there isn't a huge amount of room you dont need to go into a huge amount of detail - lets use a bit of common. Just write the obvious ones down such as skill, judgement, experience, teamwork and leadership. Good communication and eyesight should also be included and if it says so, briefly explain how you have these attributes. I dont recall them asking about how you fit the criteria of a future airline pilot so just stick to the question. One keyword is FUTURE so try and think how things may change - more complex aircraft and navigation instruments perhaps. Finally another good one is being able to think for yourself!!!
To be honest if you are struggling here, you are going to find the remaining stages pretty hard going. Sorry, it's a harsh but fair comment i feel.