As far as the meta goes, positional defense might move up in priority.
I see the issue, not with nerf/buff what with the choices that people make on what mobs to fight.
Have high s/l then do freaks/council.
High aoe/fire? fire mobs (farms)
High energy? then do rikti.
People will gravitate towards what they are strongest against, or what they built for, like with farms. I see positional defense becoming more of the preference for generalists, and s/l still being very useful since it is a very common damage source.
For the record I would also be in favor of a steeper defense curve, perhaps by an addition 5% for soft cap, it would be a smoother transition to incarnate soft cap of 59%