Once the big chase with Harvey in the cop van is done. Things are resolved: Joker's in prison, Gordon's actually alive, Harvey's safe, the girl is fine. We've had our wild climax, and then a resolution.
Clearly this was all a trick, and the story goes on... but the energy really peaked at that point and so the rest felt just a little strange to me.
Wow. You really think that?
That's odd because I think the best scenes happen right after that plot point. It's from that point on that we start to realize how this Joker's mind works:
"There morals, there code; it's all a bad joke."
[...]
"When the chips are down, these 'civilized people' will eat each other."
[...]
"You see, I'm not a monster. I'm just ahead of the current."
And of course, there's my favorite scene, the final confrontation between Batman and The Joker ("The Battle for Gotham's Soul"). I think
this should have been the ending scene (or, at least, closer in duration to it). The conflict with the ferry passengers was great and the plot-twist with Deebo was my favorite.

This goes back to my earlier comment on how I felt about the film's actual ending. I just feel that they undermined that final scene between The Joker and Batman:
"You won't kill me because of some... misplaced sense of
self-righteousness.
And I won't kill you because... you're just
too much fun.
I think that were destined to do this...
forever."
I feel that they undermined it with that actual ending, which essentially showed that, in the long-run, the Joker had won.
Like I said earlier, the whole killing of Harvey Dent (whether or not it was literally or figuratively) and they then deciding to cover it up because "Sometimes the truths not good enough" (whatever that means) is what bothers me the most.