@VINT64: I mean, that adaptation was beautiful visuals-wise (they captured the art style of the manga so well!) and still had its charm, but it could've been way better if it hadn't been so rushed - the plot threads focusing on side characters were pretty important, too, and they cut nearly all of them, as well as like 1/3rd of the main characters' interactions - and while I think that Kowloon is made of a sliiightly less, let's say, delicate matter, it's way more mysterious, so yeah, making a decent adaptation will be hard.
Out of the more recent adaptation of various manga I really liked Houseki no Kuni, although I feel like it lost some of the manga's mysterious tone. Still, it wouldn't be a disaster if Studio Orange made the anime version of Kowloon. The issue is that specialize in 3DCG, and while their 3DCG in HnK looked amazing, I would hate to see Kowloon animated entirely in 3DCG.
An excellent adaptation is the new version of Fruits Basket - as a long-time fan of the series I'd say that it surpasses the manga somewhat, especially since the manga's author actively contributes to the series as she wants to improve the elements that nowadays feel are pretty weak in the original manga. The adaptation looks and sounds good, and also retains most of the manga's subtlety. So maybe if that studio could make a good adaptation of Kowloon...?
Edit: Right, the new version of Furuba was made by TMS Entertainment. As prolific as they are, I haven't seen many of their series, though out of the ones I did, I loved Megalo Box. IMHO easily one of the best anime of the last decade or so.