How about making the CONCORD reaction a little more realistic by not having them automatically respond to aggression at locations away from gates or npc stations in HISEC space unless called for by players involved in the action?
Concept is for ships run by players only.
Add a red panic button icon to the system display that summons CONCORD once an otherwise criminal attack has been commenced and the player whose ship is being attacked pushes the shiny red button to summon help.
Lack of pressing the button would imply consent or negligence on the part of the attacked player. All other aspects of the aggression mechanics game could stay the same such as lockout/loss of sec status being attacked by CONCORD if the attacker lands on grid with CONCORD while under the criminal timer etc.