I think that giving OMDs a modest HP buff and a multiplier vs structural and ultra-heavy will do the trick. It may need a bit of a ROF buff, given how much easier it is to get starships these days. (Mostly for human players, but AIs are getting a few more starships these days too, lots more if you count exo-waves)
For the turret hull and the vs ultra-light penalty, I am apathetic on.
EDIT: Used the wrong word. I had ambivalent before, which means mixed feeling both ways. I am actually apathetic about it, I don't care either way.