A lot of the stuff mentioned in this interview has also been touched in other interviews, anyway some bits are still interesting; I'm going to quote what he's translated so far, I hope that it's fine to do so:
Interviewer: At that time, it felt like even among the manga artists and writers phone calls and faxes were suddenly flying around, saying, will they go that far for us? Director, you’ve written the script, but how was Kaworu-kun’s rather pleasing line born?
Anno: Hmm, how did I write that? It came out rather naturally.
Interviewer: It came out naturally? *laugh* What about whatever research you’d done?
Anno: There was none. I don’t read stuff like JUNE.
Interviewer: Well then, conversely, when you seduce someone, or when you are seduced, do you think that you’d like to be told something like that? Telling someone or being told by someone, “Your heart is like glass,”—did anything like that actually happen to you?
Anno: Nope, nothing like that.
Interviewer: You told Newtype, “It’s nice to take a bath, don’t you think?”
Anno: Yeah, I think it’s great.
Interviewer: What a blunt answer. *laughs*
Anno: I’m thinking of adding a few scenes. I had the feeling that it’d be good to focus on Shinji and Kaworu-kun’s story. However, I also think that, if I have the extra time, I have to make Kaworu-kun with just Misato.
The truth is that Kaworu-kun just greeted Rei by chance and he’s only spoken with Shinji, hasn’t he? There’s no need for him to meet other people, but if the only one that I haven’t made him meet up with is Misato, I kind of wonder whether that’s awkward.
Although I can’t really think of what sort of scene it’d turn out to be.
Interviewer: You said previously that that sort of JUNE-like, or should I say the sort of production that goes beyond friendship, came out that way naturally, didn’t you?
Anno: As far as I know, it’s possible that I put in a few guys like that. Otherwise, I wonder whether it might be that I have parts of me like that, myself, things that are at about that degree.
Interviewer: That level is quite a thing. *laugh*
Anno: As expected, I was called odd by the staff. *laugh*
Interviewer: Did you plan that sort of thing from the beginning? With Kaworu-kun as the last Angel at that time.
Anno: Although even in the opening he only shows up for two frames.
Interviewer: At the point in time when you created the opening, did you only have that picture?
Anno: Well, only Sadamoto (Yoshiyuki)’s rough of the picture had come out yet. It’s changed a bit, though, from the original version.
Interviewer: But is it the same in terms of their roles?
Anno: Yes, well. I’d been thinking about having the last Angel be a young man who looked like a human.
Interviewer: But wouldn’t the name Nagisa Kaworu fit even a girl?
Anno: But that’s a young man! There’s no feminine sense whatsoever, right? Because it’s Shinji and another Shinji. Since it’s an ideal of Shinji’s* that’s appearing, it can’t be a girl.
Interviewer: Ah, I see.
*ideal Shinji/idealized version of Shinji (ie if Shinji could remake himself over into the perfect person, he would be exactly like Kaworu)
Anno: Since he’s [Kaworu-kun’s] the character who’s clearing up all of the complexes that Shinji has. Well, I sort of botched that portrayal, and it didn’t come out straightforward, though. A character that is liked by everyone.
In the initial stages, he was a pretty boy who carried around a cat. The very first plot title was “The cat and the transfer student.” It was a story about transfer student carrying a cat coming to the school and so forth.
As we went on with it, in episode 24, it had already moved away from the school, so. It would have still have been good if it had come between episodes 11 and 16, though.
Interviewer: Usually, Anno-san, you and one other person are credited with the screenplay, but what sort of a relationship do you two have?
Anno: I had him do the plot after we spoke together, and I fixed up what took the form of the script once more to get it ready for animation.
Well, at that point in time, we were writing the script to send out, and so you could also say that the stories, drama, characters, and so forth that we’d thought of during previous meetings were starting to lose consistency at the time that that script finished.
We have to fix those so that they line up, so. I’m unifying it, so it’s becoming uniform, though. I help with the drama parts and so forth.
Interviewer: Who worked on episode 24?
Anno: A person named Satsukawa (Akio)-san did that. Satsukawa-san is better at—this is bad to say, but—he’s right on the mark when it comes to homoeroticism. *laugh*
Interviewer: Did you stop Satsukawa-san when it looked like he was going to go berserk, Director Anno?
Anno: No, nothing like that. Satsukawa-san’s atmosphere remains in the script. Satsukawa-san’s original script had more of that sort of meaning and was JUNE-like.
Interviewer: For example?
Anno: I’m the one who went and set it in the bath, though. In the original script, the two of them were swimming naked in a river. *laugh*
Interviewer: Were there other scenes like that?
Satou: Hmm, he had a cello, right? Together…
“I’ll play the piano, so you play the cello!” he said.
At night, in a classroom, Kaworu went first, and he was playing; when Shinji softly peeked in on him, “Can you do something, too?”
“Next time, let’s do it together.” It had that sort of feeling.
“I’ll sing a little, so…”
Anno: That’s right, that’s right. There was a scene in a music room after an evacuation, when no one was there.
JUNE is Japan's oldest yaoi magazine in case you didn't know it.
I deleted this post because I thought that this stuff had been already translated by Lili and/or Numbers-kun but it looks like it's not the case.