Have you tried offering flowers? Asking what her plans are Friday nite? Smooth Jazz?

Their relation with you should be Friendly for them to accept an alliance. Use lesser treaties like open borders, make some trade routes with them so they like you more.

They really like the open borders treaty.  In my current game my open borders treaty with the Terrans expired and they flipped from Friendly all the way to Unfriendly.  I was able to offer the treaty again, and they flipped back to Friendly.

One thing I haven't played with much is giving gifts.  I've tried it a few times and it hasn't made much difference in their relations.  It seems like that might not be as effective as it was in GC2.

Yeah, and if they ever get angry with you it is next to impossible to repair

It does not seem that you can just give the AI a bunch of techs and have it count as giving them a gift. Wierd.

The only times I get the "You have given us a gift" diplomacy screen bonus is when the AI asks for something directly as a gift, and you say yes and give it to them. (If you say no, you get the "You refused our request for a gift" diplomacy screen negative instead.)

Pretty sure you are right about requiring close relations for alliance, but a way to get there is by working up the treaty tree starting with open border. 

I you are considering an alliance V, you should definitely do open borders asap in the honeymoon era, cause it's hard to work your way back.

I have read the open border advice. It shows up in my list of things to trade with but not in the other race's items. Do I just give it away for nothing?

Finished my first game. Was doing fairly well creating a relationship with another race. We had a couple of common enemies. As soon as we defeated these common enemies this race declared war on me! Managed to beat them up enough they did eventually surrender. But it took a long while. The AI tactics seems pretty good. They will attack on different fronts and has a unpredictable factor which makes it more challenging. Still think the diplomacy AI needs some work.

Thanks for answering your own question. A game or three back, I tried the old GC2 way of giving the alliance techs away and still did not see them as a possibility in the diplomacy window.

I truly hope that the 'better diplomacy' category on the new Wish List thread ends up on the To Do list. It is very annoying to get hassled for ships and bases in someone else's territory when you can't make the same complaint, and I'd also really like to be able to threaten war if a puny twit doesn't stop hassling one of my Minor friends (or even a Major friend).