My thoughts on this are that every type can have a narcissistic or a humble person in their group. Also, having narcissism doesn't mean you're a serial killer. Your title question is very confusing to what you posted about serial killers. Most serial killers have to have both, what would be referred to as a malignant narcissist, basically they would have to exhibit NPD and ASPD together.
Though you did reference Serial Killers, not every Serial Killer has ASPD but there is a high amount of them that have ASPD. The ones that do would have to have Se. The disease's key point is, is this person impulsive? Being highly spontaneous would have Se in the first slot or second or maybe even third. Also yes, I would agree Ted could be an ESTP but I felt with his law background he had a really charismatic ENTJ feel. With Se being the third slot. Like the man meticulous defended himself in court, I'm thinking ENTJ.
Just keep in mind only 20% of people that have been diagnosed with ASPD also have NPD. Also, someone who is high with Se slot does not mean they have NPD or even ASPD.
Like I'm recently watching Dexter and he first starts out that he has ASPD or so he claims. I can't remember which version he thinks he is, Sociopath or Psychopath? Though about halfway in I'm yelling at the TV, you don't have ASPD. Like who diagnosed him? Just his adoptive father and himself? Woah, really bad parenting. Dexter does have Se but it seems to be really low maybe third or fourth placement. He's meticulous, has held a job down for several years, and is not highly Spontaneous. He plans those killings like a serial bomber would down to the last detail. Most psychopaths aren't interested in applying that degree of self-knowledge or self-betterment. Like Teddy Bundy went right on killing people after he escaped the second time. As in Dexter is really self-aware of the damage he causes to people he loves and tries best to avoid, again this is not ASPD behavior. I've lived with a Sociopath half my life, she acts nothing like Dexter. She could actually be the complete opposite of Dexter, she is an ESFP. She's grown a lot with the help of doctors and a lot of love from our family but it wasn't an easy path for her growing up. Spontaneity ain't got nothing on her. You think you might be spontaneous and then she'll go hold my beer. A real free wild child spinning in the wind with no thought to her health. Though I do know sociopaths can have an empathy switch what she feels for a handful of people and it can't be given to everyone. Example the Kray Twins loved their mother. Anyways Dexter does not have ASPD.
Again, I would like to notate not every spontaneous person has ASPD, there is a set group of points to check mark off. I had one guy tell me on a job that he thought he might be a sociopath since he didn't like very many people and had a hard time with empathy. I looked at him over coffee and told him nope, you don't have it. He asked me why I was sure. I said you're not impulsive, you don't anger easily, you're cool as a cucumber, I haven't caught you in a thousand lies, you don't take a risk, and you've held your job for over eight years now. He, of course, could still be a serial killer for all I know but he doesn't have ASPD.
FYI, weird fact. "The FBI's most feared profile is that of a female malignant narcissist. Because she will triple her male counterpart’s body count and the chances of catching her are very, very slim. Female malignant narcissists are exceedingly rare." Most will be male.
Your answer would be someone with high Se, that has both ASPD and NPD disorders if you're referring to the average serial killer.
As for plain old narcissism like your title thread stated. Any type can have them, I don't believe any would be greater or lesser in the spectrum. You could apply population stats to the types meaning there are more Sensors born in the general public would be
ISFJ and ESFJ, being that they make up 13% and 12% of the MBTI. There is more of them so they might have a larger quota of NPDs among them.