Miura and Nihei start out rather rough (early Berserk and BLAME! volumes must be painful for them to look at now) but their later material is excellent.
Manga artists who I would put on the "entertaining storytellers but have problems with anatomy and/or other things" list would be:
* Hideo Yamamoto (Homunculus)
* Kouta Hirano (Hellsing)
* Shintaro Kago (if you don't know who this guy is already DO NOT GOOGLE HIM because your brain will shoot our of your forehead)
* Miwa Shirow (Dogs and related stories)
and probably lots more that I'm forgetting because it's late.
Note that I've specifically left out the shonen and shojou manga artists and stuck to "adult" manga, not in the porn sense but in the not-about-ninjas-or-schoolgirls sense. Some of them are technically very skilled, but these books tend to be produced under extreme deadlines, which means that the quality of the art tends to suffer a lot.
If I was to expand this to include American and European comic book artists then I'd be here all night.
I disagree, I think Kouta Hirano has amazing art. Seras's boobs are wonky and his pre-Hellsing work is pretty bad but his work in Hellsing is very good, and is stylized well.
I feel silly as this is the second bird oriented thing I've posted in here and most people are looking to do humans, but I quite like this ones because it show how far one guy, Brendan Body, went to study his subject matter.
The following is a flight animation tutorial that he constructed while he was working on Legend of the Guardians, the owls of Ga'hoole.. He uses a collection of videos, still images, anatomy illustrations, and illustrated break downs to show every step required.
Some particular things I like about this tutorial is that it uses real things as examples so that artistic error won't mislead anyone, and only uses illustration in the form of simplified symbols to emphasize points, or show what photos can't (like the anatomy).
Now this one is more focused on movement, but if you want to draw wings on even a still character, you don't want to miss this in depth look. He's done the research for you and gathered it in one place. Only thing better that you could hope for is getting a real bird in front of you (which, having worked on such a high budget production, he probably had as well).