The big reason for ditching the locational thing, is that having only 2 slots per zone means that armour types that cover more resists end up much more valuable than other armour pieces with such a system. Kevlar is problematic at the moment in a bunch of ways, but one of the biggest ones, is that by covering Poision and Fire, with limited slots it ends up much more attractive than either Inq or Carbon, because it then means that one other slot can be used for energy.
That said, I'm not wedded to a return to no locational - I just think it causes many more problems than it solves.
Of course, making con resists and armour resist more equvilant would also help make this less of an issue, but the inherent diminishing returns in both systems means you'll always be best covering every damage type with every type of protection.