I am similar to Cris. Drums, Bass, Vocals, Guitars, Keys, Strings. I find that concentrating on the vocal before the guitar and keys helps because you need to place these around the around the vocal avoiding masking. This is better than trying to make a vocal 'fit in' at the end over the mix. Guitars and especially keys/synths can eat up a lots of frequency range so having the vocal present in the mix before this allows you to ensure its not getting masked unnecessarily.
However, like anything, workflow is so personal that there will never be a one-size fits all.