Get a high over knowing people intimately, yet they withhold from letting people know them completely.
If we care enough about someone we will let them get to know us completely. If you were on the receiving end of this it's understandable why you think we totally hold back.
Their social cause is EVERYTHING to them. They get really passionate talking about it.
Not sure what you mean here.
Feel slightly at odds with the world; a bit insecure about whether people like them or not.
Yes, all true.
Yep.
Easily offended with things that clash with their values.
You can train yourself to take some abuse, but not very much. In that window of opportunity where you aren't offended you oftentimes have to just go away... Very quickly. I do this when I see people drinking, doing drugs etc. I also do this when I see slutty people. You are basically correct here.
Idealise themselves as most caring (just like INTPs tend to idealize that they are the smartest).
The capacity for caring has to do with the person, not the type.
Loves to take pity on people, so they will feel protective and "loving' over them, thus boosting their own ego.
It hardly works. Most people don't appreciate being pitied, and even if I do pity them then I don't show it. It's not really an ego boost.

Why thank you kind sir.
Articulate. Extremely good at explaining the nuance of things.
Once again correct.
Values logic only if it meshes with their ideals. Ideals come first, logic is secondary.
Not necessarily. The voice of what we want to do is a lot louder than the voice of logic, but oftentimes it's best to follow the voice of logic. If you can get away with it then we usually follow what we want to do, but keywords are
IF YOU CAN GET AWAY WITH IT.
Ignores/denies what you say if it strongly clashes with their ideals and only pay attention (and even validate) what meshes with their ideals.
Nope. I'll argue for something, and say why I think it isn't right. I won't downright ignore someone, what would the point of that be?
Must feel that they are involved in a social group aimed at a greater cause in order to feel alive.
This sounds very stereotypical, I highly doubt it's true. I've never been in a group aimed toward a higher cause. The most I've ever felt alive was at summer camp when I was a teen, I felt like an individual, I had some freedoms, I was in the outdoors with friends.
Most of these points come from stereotypes, where did you get all of these anyways? If someone just followed what they themselves valued in life then they would lead an unsuccessful, difficult and confusing life.