>>297855I wouldn't recommend everything off this list (pic related), but they've all mostly got a dark and slow atmosphere similar to the original Ghost in the Shell, at least from what I've watched, so definitely look up and watch whatever catches your eye. Kino's Journey is my favorite off of the picture, so I'd recommend that above all.
Another decent place to start is Studio Ghibli. Basically everything by them is great, if you like adventure and fun. Their animation is also top of the line and is really where they shine. My favorite is The Cat Returns. Check out their other stuff though, like Porco Rosso, Spirited Away, Princess Mononoke, Howl's Moving Castle, and Kiki's Delivery Service.
What other things do you like? It'd help in giving more specific recommendations.