Thanks. The Palatine of earlier editions was a "junior
HQ" -- sort of like the Marine chaplain -- and that's the slot if thought the current codex needed filling more than the über-
HQ (eg Marine Chapter Master). If you want uberness in my homebrew, you load up the regular Canoness with
Litanies of Command and Order Relics, which make her a source of buffs for the army rather than a beatstick herself.
But unlike J3f , I'm starting from the current 6th edition codex rather than trying to rewrite it, which limits my freedom of maneuver (as a tradeoff in hope that more people will be willing to play against my homebrew). Throw out the current codex and you can do a lot more.