1] Yes! One of her core components is the loss of her left eye, alongside some fragments of her upper torso. She generally lives life free of regrets, but if she could take away any facet of herself, it would be the regret she felt at the time of her biggest loss, that of Green Fluorite. She became very self destructive after the fact, and it's taken her years to recover what she did to her own mental health. Here's a bonus image of her with her blacksmith wife to serve as a guide for the parts lost and also just because I love her So Bad
2] Fluorite's biggest weakness is her physical toughness. Being a hardness 4 with near-perfect cleavage, she is very prone to breaking even from the lightest hits. If she was even an eight, she'd easily be among the best fighters of the school just from her technical skill alone-- but her bodily weakness holds her down.
3] Ironically enough, her physical toughness is the same answer here. She's not exactly looked down on, but others definitely acknowledge it's her biggest flaw, her biggest weakness. But after undergoing reschooling with Musgravite, she's seen is as less of a hindrance, and more an equal partner. Something by her side, not good nor bad, but that should be worked around-- not against. To acknowledge, to adapt to, and to ultimately love, as its a facet of herself irregardless of what it means for her.