So I’ve seen some cyborg/fake eye/scarred/etc. Phasma ideas floating around out there, and right now, because the idea of Phasma being in horrendous pain in a Vader-type suit or robot body is too awful for me to contemplate at this time of day (thanks TV Tropes), I am here to bring you a better, happier headcanon.
Phasma loving her new cyborg body.
Phasma flexing her new metal limbs and loving how powerful they make her feel.
Phasma uploading her brain to literally every server in the First Order and enjoying freaking people out by basically being an obnoxious version of Siri that just randomly pops up to criticize your armor not fitting to proper standards.
Phasma evilly stroking her glass/cybernetic eye and using it as an intimidation tactic.
Phasma taunting Kylo and Hux by saying that she’s gonna outlive them and just replace all her body parts when they fail her. Needless to say that lots of nightmares and droid-related paranoia ensue.
Phasma replacing burnt vocal cords with new ones that make her sound scarier than before.
Phasma popping out her fake eye/showing her scars to startle people.
Phasma going on expeditions to other planets to look for newer, better parts and having a blast killing anyone who gets in her way.
Phasma replacing a hand with a blaster, just because she likes the way it looks.
Phasma turning all her pain and suffering into insurmountable strength and loving who she is no matter what she looks like.
TL;DR: Have my happy!cybernetic!Phasma headcanon because the alternatives are too awful to imagine.