I don't read so perhaps not qualified to comment , but have been the only non reader in a working band etc etc and whilst I'm always impressed when people can covert dots in sound , there is nothing like a run through rehearsal to really get tight , confident and the dynamics of certain sections right , especially when your covering really layered produced songs, with a basic 4 instruments.
With regard to the make it your own debate, I think both sides work, I love being in a band that tries to emulate well, and equally love the other creative approach. Both work for me, just different sports