Removing of AC could help a little against crit bgers in my opinion although even with 200 AC from 15-20 hex with 180-200 weapon skill the chance for hit is above 85%.
It affects not only BGers, but all characters. Wouldnt it be easier just to adjust BG dmg output rather than this ?
FYI, BGer with 200% skill, 7 str and 5 pe against 220 AC bluesuit at 1 hex got only 20% chance to hit (and thats where "In your face" kicks in). Theres just no way how to counter such build, because 300% skill with 10 pe would provide you with only 24% chance to hit at max range.