Being able to delete ship designs(still need to be able to delete base designs)
Ships are no longer flying all over zones of control/cultural borders of different races. They seem to avoid opponent's space except for survey ships which is alright.
(AI sometimes is still able to see planets/strategic resources they haven't scouted, but not often!)
The AI is building fleets more often now.
Pirates are a nuisance, which is good. 
Minor races are not building starbases.
AI less aggressive about colonizing, probably due to taking away the shared sight bug.
Five planets to a shipyard fixed, this makes the game more interesting too.
Requiring researching different planet invasion choices is great too. I think it was mentioned planet populations would start to get angry if you did not build defensive structures, but I haven't seen this happen yet.
AI offering/requiring more for trades. Though still offering a very small amount of credits in exchange for a declaration of war on a race.
There's more I'm not thinking of, but this patch improved the game a lot.
The major improvements needed I think are the AI's inability to combat or exploit culture production and the lack of defending against fleets and invasion. It needs more fleets, larger fleets, and more defensive structures built on planets. But I believe many of us have commented the AI is very poor at building on planets.
Looking forward to final release.