What kills all my interest playing CM in recent fifas is how tactics are exagerated and teams do not change their game for 90 minutes. So high pressing teams will keep on doing their thing at the 90th minute even if they are winning 4-0 and other teams sit back doing fuck all when they need a goal. How is that in any way immersive or acceptable I do not know. It's falling asleep territory for me, making me wonder why I'm not doing something else for fun, like painting a wall or two. The lack of defending/fouls & the dumbing down of passing, makes them a different sport too in my opinion. Positioning is terrible and games are just meant to be played in the final 3rd.
16 is the most fun fifa on the pitch and the most well balanced. If there's 1 thing I'd want from recent games it's the way ratings make a big difference on the pitch. However make no mistake, that's not with the offline game in mind. It's just a side effect of how huge the pay to win factor has become nowadays. So it's also exagerated. Playing against teams like Real Madrid in 19 meant they would very rarely miss a crazy bicycle kick/first time volley.
However if you go back to fifa 14 (pc version, so not on the impact engine yet!) you'll be shocked at how well ratings are implemented and how playing different teams is a whole new difficulty level on its own. This was lost next gen and its the single achilles heel of 16. So there are 2 fifa games I keep going back to. 14 & 16. 16 is definitely the most fun and realistic fifa has ever been and the variety is fantastic, it just lacks some of the depth of older titles when playing CM.