I see your point dthought, and you might be right, but i still think different. If the Altarians and the Thalans don't like each other, you shouldn't be able to ally with both. You could have a good commercial relation with both, and like both, but an alliance is something more than that.
If you take a look a Cuba during the cold war, to say an example, they were allied with the russians, and obviusly, they couldn't ally with the US too, that wouldn't make sense. And by being allied with Russia, they gained good relations with other communist countries, like China. Something like that is what i mean.
There could be exceptions, but i think it would make more sense if the races would ally forming groups rather than random bilateral alliances. Game politics would gain a lot. The way things are now leads sometimes to weird results. Once I attacked someone, and that started a chain of war declararations that ended up with every race at war with other four or five races, in a way that made absolutely non sense. It was almost like all against all. It was fun though... yeah, i don't know, maybe it's funnier like it is now.