yeah, i can understand not feeling the Ferry boat/SWAT scene as an action sequence or whatever, but the thing is that the action is sort of incidental. it's all about setting up a dramatic climax that leads to the film's solidification of The Dark Knight as a postmodern symbol of hope (the idea being that humanity can attain goodness but hope is a necessary element of that and sometimes hope is more important than the details that surround it...then TDKR brings that back to saying, "hey, but some sort of fundamental truth is important, too"...it's kind of a philosophical dialogue going on between the two films and really Batman Begins, too, in terms of what it means for a human to become a symbol).
i can't fathom any cinephile not feeling what the scene results in, that final monologue for Joker, which has got to be my favorite final villain monologue ever. i mean, when the camera/world essentially turns upside down as the Joker talks and the realization dawns that perhaps chaos/nihilism has triumphed and everything else is futile and, maybe, Joker's insanity in an insane world is the only true form of sanity...that camera move seriously goes down as one of my all-time favs in terms of the wealth of meaning it contains in a such a small, non-flashy gesture. it is an exceedingly powerful, provocative moment that's almost totally convincing in its impact, which is why it's so great that TDK manages to come up with a sufficient rebuttal in terms of Batman's willingness to soil his own image in order to combat it and preserve some sense of hope in Gotham's residents, the very act of personal sacrifice a demonstrative counter to Joker's position.
