cpu_ai / cpuai_marker / MarkingContainDistance
This is an array of values. I changed them all to 2.
Also in cpu_ai are 4 curves named:
CPUAI_MarkerReactionMaxBestDefenderTackling
CPUAI_MarkerReactionMaxWorstDefenderTackling
CPUAI_MarkerReactionMaxBestDefender
CPUAI_MarkerReactionMaxWorstDefender
For all of these, I kept the x values the same and changed all of the y values to 5. I believe this reduces reaction times to 5 milliseconds.
No, reaction time is measured in ticks, this is, in update frequency. Games update their inner logic X times each second, and this is known as ticks, or what is the same,
Hertz, abreviated Hz, which is a frequency unit. It is used in CS, for example, to update the position of a bullet fired to know if it impacts on an objective or not. This guess is further supported by the fact that in most modded CL.ini and also in later entries of Frostbite engine, in the file aidefault.ini file, we have a lane that literally says:
TEST_AI_60HZ=0 // Run the game at 60hz not at the default 30hz.
(and in this case it wouldn't be activated and would be running at 30hz instead of 60h)
If you want to know more about how ticks work in videogames, I leave a link here:
https://gamedev.stackexchange.com/questions/81608/what-is-a-tick-in-the-context-of-game-development
Having in count that one second (or 1000 miliseconds) is 60Hz, since is the frequency that the game processes things itself, 5 ticks would be 0.08 seconds, or what is the same: 80 miliseconds. Simple mathematics. If you look at the reaction times for professional players, it is way higher than that, between 300 miliseconds worst of cases, down to 150, 120 miliseconds, averaging around 250-200 miliseconds which would be a range between 20 and 9 or 8 ticks, averaging around 12-15 ticks.
This supposing the game runs at 60 Hz, but for that in theory, the lane I put above should be in your cl.ini. Or maybe not because it is activated somewhere else, not sure, don't know how FIFA internally works that much exact.
Now, this being said, I don't even think that's the real reason of FIFA defenders feel sometimes a bit too stupid. More likely it is the CPUAI_Predictionpoints, that should be higher in every single value, and in cpuai_marker, same files where are those lanes you mentioned, the lanes
CPUAI_MarkerPushPullChanceByDifficulty
CPUAI_MarkerReactionAmmount_BallDirectionChange
CPUAI_MarkerReactionAmmount_BallDirectionChangeSpeedModifier
CPUAI_MarkerReactionAmmount_BallSpeedChange
Which measures, as said, the AMMOUNT of reaction, this means, not the time, but how much commited or how much the defender reacts to a ball direction or speed change, and it should be progressive, and in general, higher. Also, the first one measures the ammount of jostle possibility by a defender, and is a good way of making defenders much more rocky and robust and proactive without need to tackle. Summing it up, how physical the defenders are.
If I were you, I'd keep the values you said of MarkerReaction as they come in vanilla or even make them between 8 and 20, but with escape values (values in the first and last y values) of 30 and 0 respectively, more or less respecting vanilla progression, maybe even doing it more varied, to prevent stacking same values to prevent having same reaction times repeating themselves, and instead having a much more wide variety. You want to have those escape values as values that exagerate like very bad or very good scenarios where the player reacts too late or inmediately, because they screwed up somehow or they did like really good. Also, tackling reaction should be slower (higher numbers) than normal reactions, because it is an action more complex than simply following and pursuiting your mark.
I hope this small guide is useful for you. I won't even say that it is exactly as I say, because man, I might be wrong, I actually know shit, and all I have are educated guesses... But is most likely to be like that.