That makes even less sense than if Luke, a leader fo the rebellion, went into the heart of the Empire and killed the main baddie and the people went "ah crap. this is on e badass. okay, I give up. you win."
Such a bold move, the death of the Emperor and Vader, would be a double whammy that would cut the empire off at its core.
It would do a heck of a better job showing how Luke has evolved from the simple farmboy in ANH, to a strong, but not almost there yet Jedi.
Even in ROTJ, he starts out on Dagobah, loses his master, and is told that he must face Vader. Thats your foreshadow of what will happen later in the movie. That sets the tone for the whole movie right off the bat, while helping the overall ending to.
I personally feel that the ending to the greatest saga ever created, is very simple, and doesnt close out well, not to mention it ends in 3 locations that have not ever been seen yet in any of the movies.
Wheres the connection to the other movies?
Ive made some postes earlier about Coruscant in ROTJ, so Im not going to repeat myself, but this would help on alot of things that ROTJ needs.