Mate, if you're not already committed to Navy or whatever you decided eventually, go to one near a UAS, do 2 years and drop out then decide on RAF/civvy etc. As for the degree, I personally would not go for a purely aviation-based one, however if you feel you can cope with aeronautical engineering then go for it, but without the maths it would be a struggle IMHO.
You need to ask yourself what you are good at, since it really does not make much difference to employers what sort of degree you actually did. If you go for the av management route, are you interested in psychology, management and all aspects of what is taught around the ATPL. If not, just go for your economics, history, politics, chemistry or whatever you have a deep interest in, because it may be better to get the broad knowledge, rather than to go straight down the aviation road all the way.
Good Luck