I've heard people say they're supposed to be very compatible with us INFJ's but of all the types of people I've ever met, the only one I've ever really, truly hated to the core was an ENTP. She was a deceitful, smooth-talking backstabber who never admitted guilt or fault and cost a lot of good people their jobs, including me.
[...]
What are some of the good traits? What aspects of their/your personalities did this person trample over, that I might not have seen? What are some of the good experiences other people have had with ENTP's or ENTP's have had with others?
I am an ENTP and I have a good understanding of my strengths and weaknesses. First of all, the person you described does reflect some ENTP characteristics, in fact I can honestly say that I was like that a few years ago (I am 19 now for reference sake). Whilst it looks like NPD, chances are that she just discovered the power of Fe when combined with a developed Ne and Ti, I exhibited similar behaviour, I was able to start fights between other students without anyone realising, I was able to get the entire year to pick on one person and then I could exploit their position of vulnerability, I have been there and I have done it.
Eventually, I grew up, I realised as amazing my ability is to preempt reactions and guide them I won't ever reach the greatness I believe I am entitled to by f**king around with other people's feelings (I know what I just said sounds bad but note the kind of attitude I had prior to this epiphany). I slowly worked out all the manipulativeness and just kept my trolling side shown when I am with close friends (or cute girls...). The worst thing about this is that nobody had a clue about what kind of person (one of my teachers realised but they were more impressed if anything) I was but as I have pointed out I have grown out of it.
Now that I am done with the bad stuff we can work our way through the juicy stuff. As an ENTP I love thinking about the present, past and the future and how they are linked. When I read about some new idea or technology I instantly consider all of its possibilities and what it could lead to. Sometimes I like to read the news to see what kind of problems society is facing today and I try to figure how they can be solved. When I am conversing with someone I get on with well, the conversation can go anywhere and it will feel like intellectual-brain sex. Note: Whilst I say conversation, it could end up like a debate...
I also like playing games, not just video games but also games in real-life like "How long will it take me to get my friend to say shut-up whilst he is on the phone to his girlfriend?" or "How quickly can I steer this conversation to be about horny naked mole rats?" but I tend to make sure that I don't do anything that's personally offend-able or at least won't permanently damage relationships.
I can also be outgoing but it can appear to be weird at times to others, I tend to be more outgoing if I have someone who is willing to join me in my adventures but that can be hard when most of your friends are passed out or hungover on a Saturday and Sunday (I don't drink anymore, it saves my brain cells and my witty remarks. Plus, the security people in the club can't see sober people apparently...).
Generally speaking, an ENTP with an underdeveloped Fe is going to suck, development of Fe can be fast or slow depending on the person. If you ever meet an ENTP like this then all you need to do is not give them the reaction they want, force them to reconsider their position (ENTPs are really good at this, trust me). There are other points of development apart from Fe but they don't create as drastic change (at least in my experience).