Id love to see a corruption level for each system for example depending on happyness or maybe a ablility to build policing forces. there could even be pirating acts shown to the player a a shortend battle ( small ship attacking a trade vessel) and techs for eample like law enforcment act on one side or freedom to arm yourself for traders. those also could have advantage or disadvantages for trading and bring posibility for dimplomacy. for example reducing the enemys money flow through sponsoring the crime in the other society.

I like the idea of having privateers.

Say build a privateer ship or fleet (that doesn't show empire colors) that leeches enemy dust but you only get that dust if the ship/fleet reaches a friendly port.

The enemy gets the dust back if they destroy it

And if it is seen returning to port it gains empire colors and gives a negative diplomacy effect.