My, you're really running out of thread ideas, anyway...

The Joker wasn't in the film for other reasons (namely the death of the character, and the actor very sadly), but the film really wouldn't have worked with any other characters. It was pretty much perfect as it was...

I look at various comics like Infinite Crisis and Justice and the villains have these huge elaborate plans but they don't include the Joker because he's too crazy. In the end, Joker always takes it personal and kills the enemy leader or something. I think that, if he were in this movie, Bane would have survived his encounter with Batman.

Batman would have been like, "Your broken, Bane. Don't ever cross my path, again." and he would have left Bane cringing in fear at the thought of facing Batman. Then, Batman would have left.

Joker would have stumbled upon Bane as he was recovering and said something like, "I wanna know how you got your scars" or "Let's put a smile on that face." and killed Bane.

Joker is actually in love with Batman.  It's true.  Google it.  Batman is the reason Joker does what he does.  In the comic "The Dark Knight Returns", Joker was pretty much a vegtable until Batman came out of retirement.  Then he couldn't wait to see Batman face to face and pick up where they left off.  Bane broke Batman, almost killed Batman, and to top it all off, he pulled off his plan.  Joker was trying to show that the people of Gotham would turn on each other like animals in the second Nolan film.  Bane showed that people would turn on each other halfway throught TDKR.  Joker wouldn't let Bane outdo him and live.

One way or another, the Joker faces Bane and Bane doesn't make it out alive.

Joker is too crazy. He'd end up taking over Baine's plans and somehow probably make him a victim. You would want pawns, not a villain who can overpower you easily

Hell, I'd imagine that Joker would turn some of Bane's men against him. That's what Joker does best. He manipulates people to fit his goals. He once tricked Hulk into fighting Batman because he told the Hulk "You have green hair just like me. We're on the same side!" Hulk couldn't argue with that logic so Batman was in for a round of "HULK SMASH!!"

I don't think the Joker would mind Bane or his actions at all. The Joker wanted chaos and people to lose all sense of morality, so if Bane helps making steps in that direction that should be nothing but a good thing.

I don't think it matters to him who sends "the message".

Joker just doesn't fit into Dark Knight Rises. I mean, you can put any characters in with the right excuse, but it'll just be that, an excuse.

But again, he'd be there for nothing more than a cameo.  Problem with the Joker is that if he's in anything, he becomes the center of attention.  I mean, look at Arkham City.  If Joker was supposed to be in Dark Knight Rises he'd have to be a huge part of the plot and that would just weaken Bane's part of the film.  That's why I don't think he'd be in there other than it just being an excuse to put him in.

He would judge the court instead of scarecrow.

After credits, kill Bane.

If the Joker was still alive during the events of Rises, then I'm afraid he wouldn't last very long. Bane is a guy with a plan, with years of preparation. In his studying of Batman and his history, he would know all about how the Joker thrived on chaos... and how he would be a liability to that plan being carried out ("It doesn't matter who we are, what matters is our plan"). Nothing could get in the way of this, especially some two-bit whack-job who wears a cheap purple suit and make-up.

After breaking the Batman, he would personally visit the Joker at Arkham Asylum, and with a swift move, break the Joker's neck. All according to plan.