What feeds in to the rating of a song? If two bands have the same manager, all other things are equal (studio, vault etc) and all band members have level 100 skill in everything, should I expect any difference between two bands for another reason? I'd been lead to believe that bigger bands get an advantage. I'm seeing a smaller band write and record songs with a higher rating than a band with one more member. So I think I'm missing something.
In addition to what you have mentioned - there is the studio upgrades and the band's fame. Studio upgrades might help you improve songs rating directly. And band's fame helps with initial song's fame level, so it get's higher chart place and more sales.
Thanks you. Does that explain why a band with one fewer member and lower fame write songs with a better rating than a band with more members and higher fame?
In addition to what I wrote, there few more things to consider. There is Skill bonus property in each band, that comes from music style of the band. This skill bonus helps keep more or less level playing field between different band sizes (and required skills) when writing and recording a song.
Then obviously there is a duration of writing song action - the more days are spent to write song, the better song.
There some randomness in these ratings when writing song, it's not a lot but it change couple percent in either direction. So yes, depending on the situation, band with lower fame and lower band members count could write a better song.