
Substitute Hero |

Cyrad makes a good point, it feels like a sort of animated object with special flavor. That said, maybe this could be worked into a player race if one treats the armor as having the relative strength of a normal body?
For this, I'd suggest removing the armor concept from the works. It's fun, but it isn't fitting for a player character necessarily. Mage Armor or Shield as a spell-like ability 1/day would be entirely in line with the concept and previous racial abilities. You could flavor that around them more fully manifesting their armor to match its strength in life. Undead Resistance is great, but this should follow the Half-Undead racial trait mentioned in the Creating New Races page. I think it's fitting for them to be close to Undeath, and the negative energy switch may reflect better on their origin. As for skills, definitely remove Stalker but keep Shards of the Past as it fits in flavor and mechanics.
So here's what I think:
Humanoid (Half-Undead) [5 RP]
Standard Abilities, Size, Speed, Language [0 RP]
Mage Armor or Bed of Iron SLA 1/day for Charisma 11 or higher [2 RP?]
Shards of the Past [4 RP]