The pirate missions are awesome! However, if you end up sitting on a pile of credits, you can definitely get some very strong pirate fleets out there.

Not sure what pirates do after they bombard / obliterate everything in the gravwell. I thought they always just stay behind and guard that gravwell much like the rebels that surround the various planets at the start of the game. Using them to backstab your ally is a great use as well, though it's a good thing you can't do that in an ally-locked game!

Pacts themselves shouldn't change standings much. I'm not sure if getting a pact locked down on both sides would cause an increase, but I do know that if the pact breaks from their side (either from the AI player calling it off, or losing enough reputation so that the pact auto-breaks), you also loose standing as well. I've encountered the bug where I get to form pacts with an AI and then, a few seconds later, he breaks it off, resulting in a loss in standing overall. Bleugh!

Haven't had any problems with getting the pacts formed in the first place though. The pact requirements have been lowered in the most recent Beta 3 fix; if both me and my partner have 11.50 standing between each other, we can get those first two pacts out in a jiffy!

I recently have seen, like today recent.  That there is a health drop bug or something.  I was playing foreign invasion 3v3 and hit the worm hole and went head to head with a hard AI and I drop in with about 5 cap ships, he has oh.... maybe a fleet of 1 cap(level 2advent) ship and 20 other random ships.  I lost a level 5 marza faster then I could realize that they had not even used there abilities yet.... The other ships of mine had perfect health and perfect shield.........I was very sad for the lost of my fine men and woman... Today is a dark day in the empire.