Nice little resource, as I'm very much into the next installment in the Nolan Batman experience, and an experience it truly is! Of all the Batman villains (http://www.comicvine.com/batman/29-1699/enemies/), I'd probably say Harley Quinn (http://www.comicvine.com/harley-quinn/29-1696/) would be the darkest, most interesting, post-Joker villain for the Dark Knight. What do you guys think? Someone else? She could be a hot actress playing the part too, a potential love interest for Batman? Also, the Riddler (http://www.comicvine.com/riddler/29-3718/) would, of course, be awesome. Or any of the Arkham Asylum (http://www.comicvine.com/arkham-asylum/34-31682/) madmen.

I'll give a full explanation for why or why not they should be...

Two Face: died ...so no

Joker: incredibly hard to replace Heath...unless they find an amazing actor, it's not gonna work

Harley Quinn: only will work with Joker

Poison Ivy: hard to do with something as serious as these new films

Mr.Freeze: possible, but not my favorite villain

Riddler: extremely possible, will work well for next movie

Ra's Al Ghul: only will work if they can involve something like Talia and the Lazarus Pits

Hush: only works with two-face

Mad Hatter: a bit too whimsical for these films

Scarface: could work...not as many people know about him though...and the whole doll thing might not sell

More Scarecrow: already been done, but another cameo of him would be nice...perhaps getting involved with the Riddler's work?

Penguin: doable, not my favorite though

Killer Croc: ...no

Bane: extremely possible, but will need very good marketing since he's not a well known character

Catwoman: really odd to do right after the death of Rachel, and after a big movie with catwoman already in it, might not work out so well.

Clayface: not that realistic....which doesn't fit these films' themes

Kaedi,

I have to say, I'm pretty much in complete agreement with you on your logic behind your list. One which I disagree with, though, is the idea that Harley Quinn (http://www.comicvine.com/harley-quinn/29-1696/) has to be a complement to the Joker. I think she can stand on her own in the next film if, and only if, the idea of the Joker is still prevalent. He may be in jail, and they just need a shot of his back in a cell to get the point across.

I can see it: Harley Quinn is a doctor in the beginning of the film, studying the Joker's case, and slowly falls for the sociopath. She becomes Harley Quinn and begins a plot to rescue her new "love." The Riddler (http://www.comicvine.com/riddler/29-3718/) shows up on the scene and is fascinated with who this Bat Man is behind the mask. Wanting to prove his intellect, he rises in Gotham as a criminal, but one who garners the respect of the city who is out for the blood of the Bat vigilante who felled the White Knight, Harvey Dent. Gotham falls into a disillusioned frenzy, and the Batman faces a considerable challenge quelling the city which he loves, though hates him.

That's why a Harvey Quinn/Riddler combination would make a great flick.

if harley was used why not have it that rachel is her, tortured into madness by the joker, I've said it before but I'll say it again two face is not dead they would not kill off such a big villian and also remember batman does not kill,bane could be a great villian if they waited a movie or 2 and did a knightfall movie(for anyone who doesn't know what knightfall is check out the comic knightsaga) the joker could be done by heaths stunt double in a mask.poison ivy doesn't need to be able to control plants she could be a leather clad seductress of men who uses herbs to control or poison people.I think that it will be a little known villian in the next movie as they did little known(scarecrow in begins) well known (joker in dark knight) and I think they will continue this pattern.

I heard it was the Riddler again.

michal caine said in a interview that it will be johnny depp as the riddler and philip seymour hoffman as the penguin in the next movie.

Always thought the idea of Edward Nygma being brought in by the police to investigate and track down Batman was a great idea for a third movie. Challenging Batman intellectually and then Talia Al Ghul out for revenge being the main villain.

It seemed to make a lot of sense to me when I read that concept.

Riddler - good, because the start of the next film will be with Batman as a most wanted criminal. Will also bring out more of the detective in Batman. Difficult character to portray though - cannot be too 'zany' - needs to be far removed from both Jim Carrey's riddler and Joker. Dark Johnny Dep could be excellent.

Black Mask - its either him or the Penguin to come in and attempt to bring order to the chaotic underworld. Would be very good to see a meeting of top Gotham officials, cops and underworld, to see just who can be trusted.

Then i think you need a physical threat to the batman.
Zsasz has already appeared in the first film, he could be a decent threat, working for crime boss and with the effects of Crane's untreated fear hallucinogen.

Deadshot is a real threat. That would work very well.

Killer Croc can be done. I think it would need to be a bit of a departure from the original Killer Croc, but Brian Azzarello had Killer Croc as a black henchman in his recent Joker graphic novel, with the artstyle very close to Nolan's 'realworld' batman. Would fit in with the gangster world.

As for the Joker, if the series is to continue past no3, then he needs to be recast. Have him held at Arkham, awaiting trial. Film 4 could include Harley Quinn or a Bane - style breakout.

!Shazam! u are a bloody genius mate, you have a truly briliant gift for movie ideas much like myself.

if harley was used why not have it that rachel is her, tortured into madness by the joker, I've said it before but I'll say it again two face is not dead they would not kill off such a big villian and also remember batman does not kill,bane could be a great villian if they waited a movie or 2 and did a knightfall movie(for anyone who doesn't know what knightfall is check out the comic knightsaga) the joker could be done by heaths stunt double in a mask.poison ivy doesn't need to be able to control plants she could be a leather clad seductress of men who uses herbs to control or poison people.I think that it will be a little known villian in the next movie as they did little known(scarecrow in begins) well known (joker in dark knight) and I think they will continue this pattern.

Rachel will NOT be Harley because, as seen in Mad Love, Harley Quinn was originally Harleen Quinzel, a doctor at Arkham Asylum and The Joker's psychiatrist who falls for him. Plus, she's a blonde. And Jewish. Which Rachel is not. (Plus put Maggie Gyleenhaal in that outfit... it just doesn't do it justice.)
My theory on Rachel Dawes is that she is supposed to be Rachel Green, Bruce Wayne's attorney friend.
As far as Batman not killing, that is definitely not true. The idea of him being the Dark Knight comes from his origins as a pulp character, a "hero" who takes the law into his own hands and is not above using firearms or killing those who he thinks are the "baddies." Which is why the police want to get their hands on him.
And as for Pamela Isley simply being leather clad and using herbs... Well where's the fun in that?