Personally, I like her last line...it's why I wanted to use it. Also, you have to remember that you have to balance out things. If you simply end the film with obi-wan walking away from anakin on the ground, and say "We know Padme Dies, we know Anakin becomes Vader, we know Luke and Leia are born and delivered to their respective places, we know yoda goes to Dagobah... why show it?" then the film ends very abruptly and there is not real climax...it reaches a high and then that's it lol...
Although you are right... there are some things that we know and can assume... like Yoda going to Dagobah...and Obi-Wan going to Tatooine... but there has to be some bridge...some continuity... some climax.
So debatebly, you could simply remove it yes.