I think I'm gonna disagree with my good friend FFF here - C is not a waste of time at all. Unless (like most people round here) you're an IT whizz or your first degree is in something that leads directly to something (eg - law), you won't earn that much in your first five years of work anyway and it will probably be tedious initially whatever you do. A year is nothing in the big scheme, and, if you're interested in your discipline it looks a lot better than me to crowded tube trains and office squabbles.
Working on the principle that you're not going to get a flying job very soon (!), it must be worth first considering what you would be aiming for if planes didn't exist. (In my opinion.) There is no job you just get, every proper career needs single minded determination. Those of us who are holding out for flying run the risk of living life as a compromise forever.
Of course, it depends what the masters in in and all that. I have one friend who needed a masters in meteorology just to get the sort of job he wanted, and one who has one in Modernist novels because she couldn't face being a secretary...