Super cool. Raises a lot of questions. I like the idea that it could be a 'backpack mech' that unfolds quickly into a full armour suit if she's threatened. Those fire sword things are flipping amazing.
( coming from 40k) She is a Primus Psyker from a paridice world which has its own psyker training program, and those "earphones" are actualy an improved Phykic hood. and those swords are power weapons.... She looks kick ass
<shrug> Its a communications unit and upper body armor. To make it wearable and useful, it emits its own anti-gravity field to take the weight and mass of the unit off her shoulders, almost floating on her shoulders. When needed, a clear polycarbonate/industrial diamond face shield lowers, and fully encloses her lovely head in its own environmental enclosure, with ion propulsion units emerging from hidden compartments. All she has to do is think, and she becomes her own spaceship...
While your idea is awesome and grounded in believable scifi I'ma still go with 'Big ass headphones'. What better way to fight in lava than by listening to Firehive by Knife Party or Through the Fire and Flames by Dragonforce? Or Ring of Fire by Johnny Cash. Burn Burn by Lost Prophets. THE POSSIBILITIES.
My thought is the shoulders are engines for bio-enhancements - should would need vastly enhanced strength to dual wield those two swords, so the arm armor is actually a powered exoskeleton. There would also have to be a gyro somewhere in the back near the center so she could keep her balance.
I love how her head unit... thing... sort of blends into her dress. The upper part of her dress because of this gives the illusion of a rigid material, but then it becomes so soft and delicate toward the bottom. Lovely!