So what I'm changing is what if Anakin was given the task of redesigning his own repairs instead of Darth Sidious holding him back. Looking into Darth Vaders problems, or at least as much as I can find on the Star Wars Wiki Pages, Darth Vaders armor was very outdated and designed to hold him back and suppress his power. To keep him on a leash the Sidious could control.
Darth Vader was incredibly heavy and fought with calculated strikes to compensate for his new heavy body and armor. Anakin was incredibly fast and agile. He used his reflexes to get him out of a bad situation rather than calculating the enemies moves. In the end that was his downfall.
So some ideas with this was Anakin still wanting to hold onto his humanity as much as possibly. His helmet would open up revealing his face at Anakins will. Because the suit was pressurized to allow him to breath, Anakins lungs were removed completely, all of his oxygen is received through his body through mechanical air passages. His heart was badly damaged, his heart was removed completely and replaced with a constant pressure blood pump. If you were to check his pulse, there would be none.
I don't know why but Jedi loved to throw their robes down when getting into a fight, I figured Anakin would still hold onto his older ways and habits as he was transformed. To replace his cape, he would retain his robe and hooded stature. All of that is removed in a fight.
Anakins neck is completely replaced, I'm not sure if in the process his jaw needed to be removed but the idea stuck in my head as something neat, feeding off of Darth Maluk and Razael from Soul Reaver. Anakin would have projectors installed so when his helmet opens up, his old face would be projected over his head to give some sort of resemblance of normalcy to him.