The intense slowdown that you (usually) encounter during a match, like when you're adjusting your tactics, is a known bug. It feels like the game has been running for over 10 hours and bogged down in memory.
Processing speed, which is when the game calculates other matches after you press Continue, is a different matter. So when people say "the game is slow" it helps when you clarify what kind of slowdown. To me, it's only really slow during certain FA/League Cup simulations ,usually in the earlier rounds where there's LOTS of fixtures. And like someone else has already said, the amount of leauges you loaded also affects the processing speed, as well as the DETAIL of those loaded leagues. For leagues you probably don't plan to manage in, it's useful to set them as View Only. Oh, and make sure you selected the divisions of the league, because by default after choosing a country, it loads up ALL divisions from the lowest possible one. I usually never go down 2 divs (so i can still have a chance if my club in the highest div gets relegated).
| 
Linear Mode
