I think the BAs gives so much more resistance, a bonus to leather jackets AC wouldint be bad. BAs are larger in size, same as metal, harder to miss, and if a bullet slide, then its called hit for no damage i assume. The things is, overally i my opinion leather jacket users should be more agile. AC is one thing, there could be even some more specific bonuses/weaknesses in each armor. Leaving still the more expensive armors better in the end. Some exemples:
Leather jacket = Some bonus to AC and sneak
Leather Armor = Chance to loot x2 hides from geckos & brahims? Or maybe some slaver bonuses (+1 slave companion slots)
Metal armor mk1/2 = Got allready laser protection, making it uniqe allready.
Combat armor = Maybe 10% less chance to be hit in eyes? or 10% less damage when hit in eyes?
There are a lot ways to make armors uniq isntead of just, bad, medicore, better, good, great. Simplicity of PVP is good for balance, but not always great for fun in the end. However, as i am concerned there will be new graphics soon? Meaning more diffrent armors posibilities.