i played before and after the new engine, and noticed not an difference in the rating but in the gameplay. And i am quite sure there was threads for new rating also with bb participation.
And yes also before they wasn't perfect, they are a hint but not the real calculation.
By the way passing is definitely included in the offensive flow of certain offenses.
even in all but not with the c, at least not with Josef tool which calculates the ratings quite well. And afaik he tested a while with "all atrocious" player to get more informations the single skill impact of different positions.
if they have an impact, i would say it is smaller then in the game.
As far as the defenses goes, sure it isn't meant to give you each defender's individual defensive stats, rather the team defense as a whole.
but when you have a mediocore(high) defense whic works and one which wasn't, then the team defense of the working one is better ;) At least in m eyes. And the rating lacks in many places like that, which alone let them only tell the half story.