I would have taken a bit more of a subtle appraoch, the "arm wear" doesnt look like arm wear....just looks like someone went nuts with an abrasive.
Personally I would have just left it alone, but the key to relicing is to make iot look natural, like the "damage" happend over years of playing and road abuse, getting slammed in the case, dropped, and just getting the hell played out of it, dirt, grime and dings more than paint stripping looks more realistic to me.
Heres my old MIM self relic that I recently sold,
I went for more "dirt" and tried to get finish removal to look as natural as I could, I used really light grit for the sanding, it took forever at aguess around 12 hours plus of sanding, but gave m,e alot more control over the pattern and IMO a more natural look.