Just some tips for filling this out:
1) Choose only skills you are really good at. e.g. If you are really good at modelling aircraft, but not so good at UV mapping and you only do that out of the necessity to get livery designers going, then choose only 3d modelling and not UV mapping.
2) Choose only your skills of which you are likely to be interested in to contribute with, now or in the future. e.g. If your day job is C++ programming, but you are only interested in testing planes, and not at all in ever programming C++ for Flightgear, then do not choose C++, but only testing.
I hope this gives some idea of how to choose from your skills: your very best and with the most interest to contribute with. I wish everyone much wisdom in restraining yourselves from ticking all the boxes

Kind regards, Vincent