I was suddenly thinking of another way Raven's arm could be modified. What if it couldn't be repaired to how it was, but rather it was altered? Took away the Overheat function and in turn gave it increased strength and such. Basically turning him into the Reckless Fist.

Since Raven does have pent up anger and regrets about his Nasod Arm, and since these feelings of pure rage about it have been starting to resurface a Rage Preventer of sorts was installed into his arm to help him control that rage and channel it into power.
However due to this rage Raven's hair will turn white slowly over the course of the RP. This could possibly allow Raven to open up even further, and could even open him up to the chance of corruption from others due to his inner rage. It could also allow him to perform similarly strong attacks without the needing to Overheat.
That or the Nasod Arm could be repaired and upgraded successfully. Allowing him to maintain the Overheat Function and his Veteran Commander rank.
I am alright with the Reckless Fist idea, and I could go with either Raven becoming the Reckless Fist because his arm could not be truly repaired to how it was and instead had it changed to help him control his anger and regrets. Even to the point where he could channel his rage into power. Or his arm could get repaired and he still remains as the Veteran Commander.