The exhuman faction choice in Transhuman comes with level 2 modified behavior, presumably a result of the character "improving" himself through psychosurgery. Now, since this is supposed to be a negative trait, it can't be something that particularly benefits the character, yet it should be something that the character thought would be advantageous. I'm trying to think up some good options for exhuman behavior modification while not being a min-maxer (though exhumans kind of tend to be min-maxers by the nature of their philosophy).
Off the top of my head I can think of increases to aggression or removing human "weaknesses" like fear, mercy, or sexual attraction. However, some of these seem to be a bit short-sighted for a more thoughtful exhuman. Anyone else have ideas?