So, I only played a 2008 manager and the newest one, FM19 so I can't really say how you feel but my first experience was that FM19 was super overwhelming. I closed the game as soon as I stared into the abyss that it truly is.
I went back to it shortly and decided to take on and yeah, it's a super deep game, and while the game gives you the option to automatize certain things (a lot, actually), you will want to have more and more control as your team grow, to the point where getting ready for a big match could take hours alone due to setting proper training for your players, booking friendlies to try out formations and a lot more. Again, I don't know how CM fair compared to it, but it's a good game that makes you want to improve and understand it more and more every match you play.
This year FM new features haven't been discussed yet but one thing that is apparent is that social networks will impact you a lot more than before. So you will also have to satisfy your fans and based on what fans meant on FM19, this don't mean 'winning = fans happy', as in FM19 it was possible to see people criticizing you for not using or misusing a player. I imagine that this will add another whole layer to building a squad and signing players if implemented correctly.