Death Knight Armor
Not that I find it a problem, but one thing lost is that it has no tie to the uncommon squire armor. I realize it overcomplicates, but it would be more thematic if it were:
Death Knight Armor
Cleric, Fighters
+9 to AC
& -3 dmg from Undead
& +1 Melee dmg
Or, even:
Death Knight Armor
Cleric, Fighters
+9 to AC
& Regen 2pts after combat
Less mechanically linked.
Or:
Death Knight Armor
Cleric, Fighters
+9 to AC
& -5 dmg from Darkrift
Undead not quite same as Darkrift, but there's some connection.
Or, if want to be very metagamey:
Death Knight Armor
Cleric, Fighters
+9 to AC
& +3 Dex
Gee, wonder why Cleric, Fighters Dex.
Nigh infinite number of other ways to go, but that's part of the problem. +2 Str is easy and always useful, where Undead or Darkrift or whatever is not.