Clayface. He can literally turn into anything, be anything, and hes just huge and crazy

Ra's has the most resources, Bane is the strongest. Joker holds the most power because he knows how to hurt on a deeper, more personal level, and has the potential to do the most damage.

Long term relationships. Batman is scared of those. He's not scared of any of his rogues, but he's terrified of long term relationships.

Joker and Court of owls

It can be any of them. Joker, Two Face, Deathstroke, Penguin and the rest of them can push Batman to the brink and that is why Batman is such a great character.

Kite Man

Himself and his attitude and the never stop I always have to go on patrol makes it so. A good example of this would be with bane , he was sick and yet like always he pushed himself past the limit and got what he deserved.

Bane and Ra's Al Ghul.

Poison Ivy I guess