Few words about stats and coaches.

2nd best ability for GK (Positioning) is trained by defending coach
1st best ability for defenders (Tackling) and 2nd (Positioning) are trained by defending coach
2nd best ability for strikers (Off the ball) is trained by defending coach
Heading is better stat for strikers that defenders, but that stat is trained by def coach

Defending coach can train Off the ball ability even though it's not ability for defenders. Same with Set pieces.
Aren't they overpowered?

That's what I suggest:
GK Coach - handling + set pieces
Def Coach - tackling + positioning + heading
Atk Coach - finishing + off the ball + heading

Rest can stay. What do You think guys? Not big change, but I think that especially for first few seasons for every player other coaches are much less useful now. It should equalize it.

Off the ball skill needed for all of the player. First meaning off the ball is the player action when not in ball possession like counter attack, quick transition and counter passing even like late tackle to make opponent player inj also call off the ball xD. Don't confuse with positioning skill. I will said like Defensive coach are same as General Coach except the tackle skill haha

Maybe Nicmo need/will revise the coach skill train in the future

i don't see any problem with the coaches..