Fast Sim versus Slow Sim Statistics

These statistics aren't even close when using the same exact sliders for the same season. All I want to do is watch the team I built have realistic games and statistics and seems impossible to achieve because so many things are off, like QB completion percentage, sacks given and taken, penalties, etc. Why can't we get realistic results? I'm not 12 years old wanting to spam the controller anymore. I'm an old head coach who wants to see the team I built play realistic football.