Why should I, the player, feel safe knowing that one of my worlds is next to a pirate base?  Shouldn't it be the other way around?  Sure you have active pirates that go on huge pirate missions.  What about small time piracy?  IMO, players with worlds near pirates should always be under threat from small groups of pirate raiders...having a world next to a pirate base should be a double edged sword, instead of using the pirate base as a free defended gravity well.

Also, these raids should persist even when pirates are turned off for multiplayer games.  This will ensure another source of experience for XP hungry capital/titan fleets, and would justify an increse in titan xp requirements for their early levels.

also, pirates that don't have phase jump inhibitors on their world are kinda lame...Make pirates more useful as a "defended" gravity well and make them seem more deadly by adding some more support structures.  Or perhaps, as the game progresses the pirate base automatically adds a set defensive building pattern over time.  So, if you don't exterminate the pirates early they will become very dug in and a very big nuisance.

This would go far in increasing their presence in the game.  As the game stands, I don't ever really fear pirates at all.  Also, any way to ensure that the pirate AI doesn't have the entire fleet move to engage one scout?