How do you get the AI to like you?

[Lemmy]

In my current game i planned play to peacefully, get huge income from trade, and get a technological victory (turned the other options off).
So now i'm trading with everyone, my alignment is evil, but i don't have the evil interface yet.
My biggest trade partner at the moment are the Drengin, and i think i'm also their biggest trade partner, i don't have any starbases in their sector, nor are my existing bases a threat to them (no culture modules on them).
Yet my relation with them is cool. It already was cool before we started trading. In the beginning there was a small war between the Drengin and me which went like this:
They demanded cash
I refused.
They declared war.
I succesfully defended my home systems.
We got a peace treaty.

But their opinion of me just won't go up.

I did get the Arceans to like me by trading with them, they were friendly to me, untill an event happened and we were at war. I took one of their planets, got peace, and now i don't how they think of me.

[Harry Seldon]

If you're evil, you'll have a lot of trouble having peaceful relations with other races. Usually, the races with a similar alignment to yours are your best bet for alliances. Evil races rarely form alliances from what I've seen and when they do they are more willing to back out on them. Other races will think the same of you when you're evil so friendly is probably the best you'll do. The Drengin don't like you either because you're more powerful than them or your powerful enough to be a threat to their galactic domination.

[Lemmy]

Bah...silly Drengin....this is all their fault then
They were the most powerfull civilization, their military was well above mine, they were either equal or better then me in the other graphs...untill they attacked me.
I switched all my production from constructors to warships.
My military rating jumped up, the Drengin lost severel ships against my starbases, resulting in equal military ratings. This got them to agree to a basic peace treaty, but now i'm keeping those ships around just to defend my sectors, which also was their inteneded use in the war.
The Drengin is still fighting some wars, and is losing and building ships, so their progress slowed down, and i continued to build and upgrade my starbases in peace. Also gained some new trade routes.
All this resulted that i am now equal or more powerfull then the Drengin in any area....except military, i think they're getting the upper hand there now.

[Harry Seldon]

You'd better attack them before they get an advantage. I made the mistake of waiting too long and now I'll never catch up to them. I'm really just waiting for them to come for me at this point.

[Lemmy]

Nah, they won't get me, the relations are only cool, and the couldn't defeat me anyway.
I was weaker then them when they first attacked me, and i survived (with ease), now i'm at least just as strong.
And now with my starbases all enemy ships have at least -2 speed, and my ships have +12 offense....those starbases are really good to dig yourself in.
My home sector got 3 starbases, they got full defense, full production, and full trade, i'm now upgrading the military modules.