ok i think i stated the topic a bit wrong...
My intention was to get amine that ended before the manga ended and left the series hanging without a conclusion, like Hunter x Hunter, 07-Ghost and Claymore
not so much your fav shows that ended when they were supposed to like Trigun Cowboy Bebop ect
Granted i wish we could get a redo on some like Kenshin, the manga ending was SO much better then the way they went with the anime after the Shishio arc
He did follow the original Trigun manga with another.
Besides, even if the material does end, if it concludes on a non-ending then your left with a certain emptiness.
Though I disagree with people that want to continue series for the sake of just having more of it, regardless of whether they have already achieved catharsis in the plot. Code Geass, for instance, had a beautiful ending, if they wanted to continue they could do a side story or the alternative universe they developed in manga. To force the continuation of the main story-line would be distasteful.