Hi, I take psychology A-Level (but I don't take any language, so I might be biased), but I really love it !!
I find the subject to be really interesting and sometimes when you come across something that fascinates you it makes the subject so much easier to learn from and revise and whatnot, and fortunately a lot of the stuff is fascinating. Personally, I find looking at the way people might respond because of situations really cool because of the way thought process work.
You mentioned you're thinking about English Lit too (which I also take), and I mean depending on the texts you study, psychology ties into it quite a bit. For example, we're studying Hamlet where the Freudian complex could be used to explain Hamlet's feelings and actions toward his mothers marriage.
Obviously it's also good to take what you want to do in the future into account, however, I never knew (still don't) what I wanted to do, so if that's the case for you, pick which one you'd rather do based on your enjoyment of the subject.
But if you really can't decide you could take 4 subjects and then drop one (or continue all 4 if you can !!)
I really hope this helped !!!!