What's great about Ghibli is that they DON'T do sequels! It makes their films feel unique and not cheap and subpar cashgrabs. The one and only Ghibli film that could possibly benefit from continuation is Nausicaa (I know it's technically not a Ghibli) as original film was only about 1/3 of original manga. I hope that Ghibli will never sink that low to make a sequel (other than Nausicaa).