We know they had ideas for sequels, which turned into only one sequel
Agreed. The original loose ideas thrown around by Goyer and Nolan was for a Joker film, then a subsequent sequel where Dent is burned and turns into Two Face during "the trial of the Joker". I remember reading the interview with the two about this very specifically, possibly Empire magazine?
Anyway, they ended up as you said just condensing it into one film, The Dark Knight, which IMO works better. And also makes the overall trilogy less contrived than say pre-planned out sequels with hints dropped in about future films, ala Marvel Studios. Nolan and co. really threw everything they had into the film they were making at the present time.
It makes the whole Nolan Batman franchise and trilogy really organic from a story and character standpoint. I know for sure that there was never any solid plans for a 3rd film after the condensed version of TDK, and that TDK Rises story hadn't been hatched until late 2010. Prior to that, Nolan was debating on whether there was a even a story to tell, or a reason to come back again without things being stale.
I think, when it comes to BB, Nolan is only being coy. But when it came to a threequel, Nolan was being honest.
Agreed.
We already had a start of some kind of rise with Scarecrow being used, so I never bought the idea that Nolan wanted to start the "rise" in TDK.
Not really, he fully intends for the escalation of theatrical crime in the sequel to BEGINS. It's stated in dialogue for christ sakes. He's Dr. Crane for much of the Batman Begins film. He goes nuts in the 3rd act. Prior to that point, even though he experiments on the inmates of his nut house, he has very sane motivations of wanting to get paid. Holding the city for ransom.
By the start of TDK, it seems like he's deliberately selling his tainted drugs not for money purposes, but to freak people out and make them go crazy. Kind of like a Nolan / comic book movie version of a bath salts supplier. Even the mob is obviously upset with his crazy psychedelics. He isn't totally theatrical either, it seems he uses the scarecrow mask to just hide his identity.
It isn't until the Joker that we get a true villain for Batman who uses complete theatrics like himself, who fights for the sake of it. And doesn't have a true end to his means. Thus the rise of the freaks. The Joker even destroys the mob on his own, through his manipulations. Just like in The Long Halloween.