However, I think a certain amount of irrationality and jumping to conclusions and so on is actually an advantage we've evolved. We're never going to be able to get enough data to fully understand a situation. Quite regularly you have to make choices based on limited understanding. And our ability to make conclusions and connections, while it regularly goes awry, is also, by and large, a very useful adaptation.
Ever tried to make a computer function? The million ways things can go wrong if not all input is correct and present is enough to drive a person crazy. I'd rather not have my brain work like that.
I suppose the Vulcan option you're proposing is an interesting one...give up emotion and irrationality in favor of peaceful relations. Certainly Star Trek addressed that option periodically...but heck, even Spock would periodically be emotional or irrational. I don't think any functioning sentient being can really avoid it. Personally I'm with Spock when he says that logic is the beginning of wisdom, not the end of it.
Dear Lord, I am a nerd.