I know it doesn't make sense, but for Psychology, A Levels in the 3 sciences and maths are considered way better than A Level psychology. I know as my dad deals with UCL psych admissions.
I don't have much else to add, as I do neither media or film. I'd pick what you enjoy more and most definitely look at university websites to see what they advise. You may find that doing subjects like Art, History or English Lit may be recommended over film studies, even for a film studies course due to being perceived as more academically challenging. Southampton lists English, History, Philosophy and Film Studies to be preferred subjects for their film studies course.
I'd certainly consider doing at least one facilitating subject. These are English Lit, History, Geography, MFL, Maths/ F maths and the 3 sciences. Solely because your other 3 subjects are likely to be perceived as softer, though they may seem more relevant to the course you want to study at university. Again, this may depend on the uni.
In regards to doing 5 AS it usually doesn't help. But having both media and film may help, so definitely check with some unis.
As for how much spare time you have, this depends on you. I'd say aim to do a couple hours work a day independently at A Level, maybe more as exams creep up. You have free periods now, so you can do revision then. You'll find if you have 2 free periods in a day, doing 2 hours then and 1 hour at home is usually enough to do well.
Good luck with your GCSE Results.