Interesting ideas, and I like the GHAO option, makes the feats a bit better. I should have thought of how +2 actualy effects crits, since I do love stats.
SO...
Heavy Armor Optimization [General]
Through focused training and practice, you are able to get more benefit out of heavy armor.
Prerequisites: Armor Proficiency (Heavy), BAB +1
Benefit: When wearing heavy armor, decrease its Armor Check penalty by 1, and the armor bonus of the armor is considered increased by +2 versus critical confirmation checks.
Special: A fighter may select this feat as one of his bonus feats. Heavy armor made from Mithril does NOT count for this feat.
Greater Heavy Armor Optimization [General]
Through focused training and practice, you are able to get more benefit out of heavy armor.
Prerequisites: Armor Proficiency (Heavy), Heavy Armor Optimization, BAB +3
Benefit: When wearing heavy armor, The armor bonus of the armor is considered increased by +1, and DR is increased by DR 1/- (to DR 1/- if there is no DR on the armor).
Special: A fighter may select this feat as one of his bonus feats. Heavy armor made from Mithril does NOT count for this feat.
How's that?
DR stacks, so DR 1/- I think works well. It seams like a lot for the second feat, but given that it means you need to be wearing heavy armor, and you can't get Mithril, I think it works fairly well. You also can't sleep in Heavy Armor under any circumstances (Endurance lets you sleep in Medium Armor)
Man, I almost want this feat for Juliana... though not quite enough to surplant Deep Impact.