A single EC-89 can distract the main unrat force in the Connie sector. This allows another player to simply stack avs and kill the connie rather quickly.

Short video of my EC-89 keeping the unrats busy: https://www.youtube.com/watch?v=VskYEQAwJLw

tacking on to this, regular unrats that are guarding wormholes have similar behaviour, especially if you manage to stuff yourself into an asteroid.

I found them to do that the first time I went after their dent, came back in an MGC and simply killed them all. This is the problem with giving them a leash. You can sit just outside the leash and wipe them out. If you simply cut the leash then you can just set a hound on turbo lock to lead them away.

What might work is to have them only dispatch a few fighters to perpetually chase someone.

2 for an ec, atlas, xc, etc

4 for a vulture, centurion, marauder, etc

and half the swarm for a goliath/dent

This allows them to retain a reserve, something military commanders have known to do since the days of ancient Babylon.

The big problem I see with this is the amount of work it creates for the devs.

I wasn't going to make suggestions here. But since someone already did that: use a similar mechanic like a hive mission (when a player is in the mission). Everyone who is in the sector gets an unleashed raptor or two on them. Kill the raptor and it comes back in two minutes.