Have you thought about switching language for lit? It's more respected, you'll get 2 facilitated that way. I do Philosophy and Ethics. I think they're equally respected. Psycology is harder though. R.S exams are usually quite easy, the questions repeat themselves, I'd done all my R.S questions before the exam. You can get a really good grade in it if you try. Psycology looks more impressive though, and you may find it easier.
In the end, do the one you enjoy more. That's really important. Which one came in your head? Go with that one.
Have you considered biology? Hard work, but so fun! I never realised how intricate the human body is. Again looks really good, having great synergy with Geography and Maths.
Good luck. A levels are great. Mine are History, English Lit, Biology and R.S