Behavior is an outcome of the ideology, if you are benevolent you are going to treat people nice and you are going to help them whenever you can. Malevolent people help you if that helps their plans (they are malevolent, no airheads) and their alliances serve no bigger purpose than reaching specifics goals (galaxy dominance, monetary gain, making an army of killer bunnies, as you seem fit). The problem right now with benevolence and malevolence is that they lack of substance, think of Darkseid that guy is malevolence in its pure state (kind of) but he is no idiot (kind of) and he uses good guys to his end (he even leaves them alive just because of that). But there are other villains that are just focused on killing everything without reason nor logic (Doomsday, for example). Benevolence also has its own shades like doing good no matter the cost (crusaders, anti-heroes) and doing just good deeds like pacifists
.
Now, If you get ride of pragmatism (the way it is now doesn't make sense to me) and you add two more traits like passiveness and activeness you can have a 4 axis plane that can suit each race with the right amount of malevolence and benevolence that fits them better:
"Arceans are a benevolent race with a hammer/rocket launcher in their hands, they prefer action rather than words. You can see them as a benevolent and active guys."
"Altarians are a benevolent race that their motto is think before act. Benevolence and passiveness in action."
Right now we have 3 trees but with that idea you can have 4 trees with 5 special perks/traits (one for "neutral"), for example.
Trees:
Benevolence/malevolence = diplomatic and influence traits.
Passiveness = research/defense traits
Activeness = movement/attack traits
Perks/traits (as passive bonuses):
Benevolence - passiveness = +10% diplomacy +10%weapon cost
Benevolence - activeness = +5% weapon damage -10% negotiations
.... etc ...
The system right now also works with that idea nicely. 40% benevolent and 40% malevolent = 100% pragmatic (neutral or how you wish to call it, you just did what fit you the most without being bound to a specific ideology a.k.a pragmatism). So, a ratio 4/1 benevolent/malevolent and 3/1 activeness/passiveness makes you a "Benevolence - activeness" civilization. How that is going to work with the AI? Much sweeter, if a civilization is more "Benevolence - activeness" they are going to make wars more often and help you in a more active way (fighting at your side) while passive guys help you sending resources and techs rather than fighting (they can if they have).
What do you think?