There's something about changing Sprint and Acceleration that spoils the fun for me. I think it's because when I wasn't used to FIFA 16 yet, I had to make the CPU slower to be able to win and was "shouting" here that this is the only way to balance the game. Then I got better and played with everything on default, even pass error, to make it a bit challenging (but still won the champions cup in 2 to 3 seasons starting with a 72 team...) - and admitted my error in shouting for changing the speed.
With all due respect, I played on Legendary with Sprint at 50/51 and Acceleration at 50/51, and I could still beat the CPU easily. In career mode, our players get good form easier than the CPU players and games become easier. Kick offs are different because there is no player form.
While I did make the CPU slower when I couldn't beat it, I really dislike the idea of making either side slower or faster now. Pass error is the only stat that I can personally tolerate simply because it's not realistic but if 'realistic' means 'easy to beat' then I will even let the weak teams play like Barcelona.
Just making them faster would not be a solution for me just because I am beating the CPU (as it wasn't a solution to make my players faster when I was losing).
I guess my point is that changing a player's speed is not realistic because you are changing the core value of the player. Changing pass error for the CPU is more realistic because out of the box, CPU doesn't pass based on player stats.