Main problem of this players is they are logged in to many turmament than they can handle, Some players play more than 4xx games in arena and they can handle them (they play slowly but they play in time limit).
Some solution to solve this :
Limit turnament inscription for low karma player (maybe already the case)
Limit simultaneous inscription on schedulled turnament to avoid than player with positive karma log in in to many turnament and not handle them.
For exemple if you can only log on 3 no already starting turnament, active player will not be realy impacted because less active player witch log in to many turnament will let place for them.
Some solution to solve this :
Limit turnament inscription for low karma player (maybe already the case)
Limit simultaneous inscription on schedulled turnament to avoid than player with positive karma log in in to many turnament and not handle them.
For exemple if you can only log on 3 no already starting turnament, active player will not be realy impacted because less active player witch log in to many turnament will let place for them.