Aside from the listlessness of her wings, I think their rooting into her gems are beautifully done.
Well, in my headcanon, the crystals are Exspheres*, which are a kind of evolved lymph node that acts as a mana production gland. They're made of the same composition as Chaos Emeralds, which consists of Eco, Tiberium** and Phazon. They convert absorbed*** Psi energies into Magic.
*Related to but different from the Exspheres in Tales of Symphonia. The ones in ToS are artificial, and as such are technically Chaos Emeralds. Cruxis Crystals are the same as the Crystal Bearers' crystals
**Specifically the Taelon crystals, though the Tiberuim biomass is present in Exspheres but not Chaos Emeralds
***Psi is absorbed through the skin, especially around the navel
