Did your NCS not send you a list of documents to bring? If they haven't yet, then they still might. Aside from the ones they ask for, if you have any other documents related to your application, by all means bring them, but they probably won't be asked for or looked at. My thinking has always been that it's better to have something and not need it than to need it and not have it.
I applied under ILR + spouse of a UK citizen. They looked at/copied the following documents for me:
- Both of the passports (1 current, 1 expired) that I have held in the last three years.
- My biometric residence permit showing my ILR.
- My marriage certificate.
- My Life in the UK test pass letter.
- My husband's passport.
- Letter from the university at which I am currently studying, confirming my student status.
- My university student ID.
I'm exempt from the language requirement, but brought my UK degree certificates, as well as all documents related to my employment during the 11 years I've been in the UK. They didn't ask for any of these things, but I felt better having them. If you are not exempt from the language requirement, then you will obviously have to bring documentation showing that you fulfil it.
Since you're not applying as the spouse of a UK citizen, you won't need (3) or (5) from my list. If you're not a student, you won't need (6) or (7). If you're employed, you might be asked for your employer's PAYE code, and it probably can't hurt to bring payslips, a P60, or a letter confirming your employment, though if there isn't time to get the documentation, I wouldn't worry too much, as long as you have the information needed for the Form AN itself.
Good luck at your appointment!