It is a long, bloated film, that is also incomplete. I am going to forget the ridiculous, exhausting and repetitive last part of the film. I am just going to talk about the stuff before they get to Mount Doom.
Everything is the end of everything. Everyone has to do it. Everyone has to either die or almost die. You know when people complain about Snyder's slow-mo? That is how this film plays out. Grab a Hobbit, look to the sky and shed a tear because everyone is experiencing the most poignant moment in the history of mankind, one after the other after the other.
Now this wouldn't be fine under any circumstance imo, but at the very least they could have spread this out with some actual plot work. It also does murder on the characters. Everyone other then Frodo, Gandalf, Gollum and Sam are reduced to caricatures, with Gimli, Legolas, Merry, Pip, and Eoywn getting the worst of it.
The battle itself just doesn't work like Helm's Deep does. With Helm's Deep they did a very good job of structuring the battle. You get a sense of progression, what is going on and what it means when each position is lost. Here, there is no focus. If Gandalf had been a general instead of simply a guy running around fighting with his sword, it would of had potential. After all it is set up to be a battle of generalship between the Witch-king and Gandalf, but that is ignored and the cgi creations just sort of go around hitting things.
I think nothing is worse though then what happens to Aragorn. He is almost sidelined, made anything but irrelevant. This is his ascension, but it is as if all of the important Aragorn bits ended up on the cutting room floor or the EE.
Also, so many of the important character moments are left for the EE in favor of the long, drawn out ending.
Then there are just the weird decisions. Legolas surfing, Denethor running a mile on fire just so he could fall a long ways, The Witch-king's promise to break Gandalf being completely ignored (and in the EE being terrible), whatever Aragorn is suppose to be doing with the troll, every Arwen scene.
I always found those to be "crowning achievement" awards, like the Oscar. Good job for the series type stuff.
A lot of the general public and movie goers would probably tell you RoTS is the best SW films, and that is probably after actually having seen SW and ESB.
t:
Oh come. When the groups all go off in their separate directions with purpose and Aragorn sends his "brother" off, you have the end of a film. When Isengard falls and Helm's Deep saved, you have the end of a film.
There are storylines and agendas that presented and resolved before the end of each film.