Pass completion depends very much on your tempo.
In general Low tempo = Better pass completion, less chances, but better shots on target percentage.
It also depends on mentality: If your players have very different mentality they won't have to many passing options other than direct, and completion will suffer.
IMO (and it is oppinion based cause it depends on so many factors) if you play direct and on the counter, pass completion as low as 65% is acceptable. If you play normal mentality 70% is acceptable. If you want to dominate a game 75% is acceptable.
Tackling percentage:
IMO It is almost impossible to say something meaningfull here. For example you might win 80% of your tackles and still lose heavily. This happens when you are under heavy pressure and your defenders (who are good tacklers) make and win a lot of tackles. And a low tackling percentage could simply be down to your strikers doing the majority of the tackles because the ball is mainly in your opponents half.
Cross completion: If you play with wingers do not expect completion above 30%. The only way to get better percentage is not to play with wingers.
IMO wingers are the only flaw left in the current engine. They do not work quite as well as they ought to. In general a deep cross from a FB is usually much more efficient than a byline cross from a winger.