I rather like the fact that Ghibli movies rarely have sequels.

The exceptions are "Mei and the Kittenbus" - which few of us have ever seen since it's only been shown at the Ghibli Museum - and arguably "The Cat Returns", which may or may not be a sequel to "Whisper of the Heart". (More like a spiritual successor, to my mind.)

I find that the best stories can be told succinctly in one telling.