[Glathannus]

Here's how I'd rank the Studio Ghibli films I've seen:
1.) Howl's Moving Castle
2.) Princess Mononoke
3.) Nausicaa
4.) Kiki's Delivery Service
5.) Spirited Away
I wouldn't re-watch these, but I don't regret having seen them:
6.) Arrietty
7.) Castle In The Sky
Ugh:
8.) Totoro

Not everyone is going to agree with that. It really depends on how much weirdness I can take before I would consider a film to be "too weird", versus how much I like the film's environment. Spirited Away is the weirdest one of all. Howl's Moving Castle is second-weirdest, but I like its environment a lot more. When I first saw it, I wouldn't have said that Howl's Moving Castle was my #1 Studio Ghibli film, but it's grown on me with additional viewings while Spirted Away hasn't.

Nausicaa kinda felt like Princess Mononoke Lite to me, but that still makes it better than most of Studio Ghibli's other material.

Guys might consider Kiki's Delivery Service be boring because there's nothing weird about it, and there's no villains or conflict, but it gets bonus points for the most beautiful depiction of European-esque society I've seen from Studio Ghibli other than in Howl's Moving Castle.

There's nothing weird about Arrietty, but it doesn't feel quite unique enough, given that we've seen so much other animation (usually American) from the perspective of tiny rogue entities (usually animals such as mice) surviving amongst mostly-oblivious humans.

Castle In The Sky feels dated, due to the combination of how the characters are drawn, and because the storyline bares too much similarity toward a dozen other (mostly newer) storylines I've encountered. But at the time when it came out, I'm sure people took this film seriously enough.