Are you willing to take advice from a bloke who got expelled from high school, so doesn't have even a single, solitary GCSE? If you are, then my advice would be to take whichever subject will give you the most pleasure to study. With your science requirements, your courses are going to be interesting if your mind works a certain way, but there's an unavoidable dryness to the subject matter, however cool and exciting people like Stephen Fry and Dr Ian Stewart (TV Geologist, not the one who co-wrote the Science bits of The Science of Discworld) make it seem; absorbing the knowledge is - not to put to fine a point on it - as dull as ditch water. And the ditch is in Milton Keynes.*
It's important that at least one subject each day is something that's going to make your brain switch on in a different way, if only to avoid burnout for hard science. Whichever of the options you've mentioned is the one that excites you the most, is the one that's going to the best option for you. The travel to the language lessons is hardly that big an inconvenience if you really want to learn one of them, you'd be amazed at how quickly it becomes a part of your routine. Take whichever one will allow you to relax a little, away from the endless procession of equations and mathematics you'll be swamped by from the hard sciences.
Whether that means learning a soft science
like psychology, or learning how to order ten grams of ham in Spanish (Gongame dos gramos de jamon, por favor) then that's the correct choice.
*Beside a motorway fly-over.