I'm probably alone in this, but I'm really not a fan of his work... I think the anime shows great depth and imagination, but I find it a bit disney-esuqe for my tastes... I find it's quite suitable for children, though I'm in no way insulting your tastes here... "whimsy" is just not my cup of tea.
I'm more fond of movies like Perfect Blue, the story of a Japanese Pop singer who quits her singing career for an acting career and finds herself doing more and more AV-like work in her films, such as the simulation of rape, etcetera...
She's consistantly stalked, and becomes her own murderous double.
I'd also recomend the Patlabor movie, and, for the visuals, the Apple Seed movie... Spirited Away just didn't do it for me.
There are some others which escape my memory at the moment, but unfortunately, the American audiences can't seem to take Japanese animation seriously... though they seem to go gaga for things like "The Incredibles..."
ps. Steam Boy rots... (after Akira, you bring us this!?)