excellent work, as always, Pyro. i wish i had the art skills you have.
now...to go in depth...
for starts, the wings remind me of the Aerosaur concepts you showed me. interesting application.
the first flaw that strikes me is the chest plate. in the pose, it doesn't cause a problem. but it would be horrifically uncomfortable in normal movement. it'd probably work better if it was more rounded to the shape of the torso, with perhaps dips in the armour where her arms would be likely to go.
another issue i see is the gun. the way she holds it. for it to be stable enough to shoot without flying out of her hand, she'd need either A) bigger hands, so the back of her palm can hold the gun in place when she fires, or, ideally, B) one of her fingers acting as a thumb, similar to how she's gripping the sword.
aside from those two, the only things i think could be improved are the shape of the leg armour [too snug IMO. doesn't give room for the leg muscles to flex and relax when walking. the upper leg in particular looks somewhat uncomfortable...but then i have a bit of a habit of giving my characters big thighs, so it might just be me >_>]. the lower leg of the armour looks somewhat uncomfortable around the joint of the 'ankle'. if we were speaking from a practical point of view i think the armour would be cut a tiny bit higher to give room to move, so it doesn't dig into her ankles when she runs or goes for long periods of time with the armour on.
those are the only actual flaws i can see in the design as is. aside from that, design improvements like perhaps a bigger tail blade and arm blades [makes for good close combat defense weapons if she's somehow disarmed in combat. stabby stab

]. the wings could use a more flexible design IMO. i can't imagine her navigating through doorways very well with wings as seemingly stiff as that. maybe design joints into the bending points and make the various pieces of the wing overlap when furled? or design in it such a way that they can be closed to form disk-like plates on her flanks that can open up to produce wings when needed? i dunno. just throwing out a couple of ideas for you.
that's all i have to say from a design point of view. artistically, it's outstanding, like i said. i'm a long way from reaching this quality [oh, how i wish there was a shortcut D:].