I've just seen this movie in TV. I'm not a fan of this genre in particular, but I thought this one was really good. Because I've seen the film for the first time, I focused on the story rather than typing the characters. I'd be interested in types if you have an idea. I'll just give my guess even if I'm not sure about them, there is also not much to go on regarding some of them.
Trevor Reznik - maybe LII, even though he is difficult to type because of his mental problems. Could have been very different before.
Stevie - SEI, maybe caregiver style, doesn't seem to be too extroverted
Marie - ?
Ivan - probably sensing, maybe a reconstruction of Reznik's former self
Miller - SLE?