At first look this looks pretty good, but on closer look there are several areas which I could see improvements on.
Mostly gripes with the head
The direction she's looking toward looks uncomfortable. (side profile on a forward facing torso) some tilt on her body towards the right would be nice, something like what you have on your wargreymon piece.
Lips look thin, again because of the side profile angle (bottom lip looks better because of the. Some defining protrusion where the lips are may help.
Assuming her helmet fits her head snugly, her head is really big/long, judging by the nose which starts from just below her helmet. Also, according to that, there should be some empty space in the front, to allow some space for her nose.
Her 'helmet' is more of a mask. It doesn't actually cover the back half of the head, but perhaps this is your own take on the headpiece. [link]
Can't really tell where the light source or sources are in the picture. The glint on some areas seem to suggest it's directly above her, in front of her, but more of the shadows point it to somewhere above her, between her back and wings, right above her shawl or something coils thrice around her hand. Her shawl/wings probably will pose some problems with shadows.
I think there are too many swathes of black throughout. Small areas like her fingers and shawl should just be darker instead of outright black.
Her arm looks somewhat weird to me, because of the size difference on the forearm versus her upper arm, but it might be perspective. The bulge below her thumb looks awkward as well.
Overall I would consider this an above average piece of work, but it doesn't feel like it has as much effort or eye on the details put into it as much as your other pieces.
Hmm her breasts appear a little flat (don't worry i'm not being a perv i got a bf) her wings as well but i think that has to do with the simple colors used. The pink cloth definitely has depth that i love. Also it would be awesome if you could do like an evolution from Angemon to Ophanimon. Power things up
An excellent homage to the anime, especially the first season and early Digimon characters. Compared to the official artwork this is an excellent and true rendition. The only thing that bugs me is that her chest seems to be larger on the left (her right) than on the right (her left). The armor covering that area also seems to have a different mold on the right than the left; the left being the closer of the two to the official version. Still, this is an amazing piece and I hope to see more anniversary images from you for this series ^^