It is.
...Both Protection from Chaos/Evil/Good/Law and Shield of Faith grant deflection bonus.* I already have a note to GMs not to allow my class in Gesalt, and since I already have a way of discouraging one level dips into my class for AC, that takes care of half of that problem. Going Grace-Gift 12**/Cleric 1/Grace-Gift X is not an issue since this is the party member that everybody buffs GLADLY if they are RPing a Wisdom score above 12, and I hear that AC becomes slightly less meaningful at those levels anyway in normal play.
*Magic Vestment gives an Enhancement bonus, so that is pretty much irrelevant since enhancement bonuses make NO sense in this case.
**The minimum level of Grace-Gift to get an option that ISN'T Deflection.
tl;dr I am pretty certain I want to start with Deflection bonuses. As for what comes next... Sacred/Profane
I am aiming for something... more powerful than most Tier 4s.
The class concept I am working with here is... really odd. Think "Defender (Buffer)"... crossed with "Defender(Tank)"... and a small splash of "Defender"... and then with a few things to do that make it useful outside of combat.
Their offense is equivalent to a commoner, EXCEPT when making some types of AoOs, at which point, at 3rd level or higher, they start being as skilled(or more so) as a paladin, but without the per-day or alignment limits on their smite.
All of which to say that being really hard to hit is actually PERHAPS part of the picture.
For anyone who still needs a more specific idea see The Grace-Gift.