There was recently the question
Making all elements clearly audible in the mix
Which seems better suited for Sound Design stack exchange
There was another question related to mastering which I reccommended be moved to sound. stackexchange, but there was some debate in the comments about where the question belongs, so straight up:
Where do Questions pertaining to mastering, mixing or Production belong, and are they allowed on music.stackexchange?
Thinking about it now, it seems that there could be some value to having mixing questions on here, when it comes to things like how to mic up an instrument, doing live eq etc, but does that extend to doing an album mix, and if not, where is the line?