They looked at everything for me - and to be honest, if you have the grades this is what's most important to universities (which I disagree with, but that'll lead me onto a rant). So just focus on getting your grades.
I applied for Psychology alone. However, I know that if you choose a Scottish university (such as Dundee, Aberdeen etc), you can pick lots of modules outside of psychology such as a modern language and you don't have to 'pick your degree' as early as you do at an English university. If you're in England, maybe look into a psychology and language joint degree?
In my experience, you're very guided through everything so don't stress about falling backwards. You will be taught those 'extreme' independent skills way before you need them which is mostly when you're writing your thesis in final year. In your undergraduate psychology degree, you will carry out your own research in final year usually (but you should check with your university anyway) - but you WILL be 100% guided through this and have a supervisor to help you as well.
I'm sure you're aware that a psychology degree gives you BPS (British Psychological Society) accreditation. With this, you can go forward and apply for an Masters in Forensic Psychology if this is what you want in the future.
Honestly, I wouldn't say you need to read before you start a psychology degree. Maybe brush on your research methods (did you take psych A level?).
Any more questions just ask