There just is nothing worst than a even such as:
"every planet within 2pc of star system X has it's PQ increased by 12".
This just means that something between 20 to 60 new high grade planets have just become available. If you're on the receiving end, you'll end up too powerful (if you manage things well) ; if you're on the other end of the galaxy, you'll almost sure to lose to a reasonably proficient AI: there just is no way to compete with a collection of PQ 12 to 25 planets packed together.
Ther may be other such events, but I think this one is really one of the worst. When I get it, I just have to reload the game.