I am of the belief that a STRONG dog does not need alot of socialiaztion.....their genetics is all they need in order to be a tempermentally superior animal.And really, she has had no socialization. The only time she's out in public is at the vet's office. I'm always reading in here that they don't NEED socialization, they only need you. I don't know... I just feel like such a huge failure.
I am of the belief that through much conditioning and exposure i.e. "socialization" a dog mediocre in temperament, can be made stronger.
I am of the belief that a weak dog, no matter how much help (conditioning, exposure, socialiation) will never be a strong dog...perhaps with ALOT of work, mediocre at best, but even that is a stretch...you can only do what is within the paramaters of the dogs genetics.
One thing I would not do is force Nala to greet strangers. That could actually make her worse. If you are determined to try and help her you could try motivational style obeidence (hand feeding their meals during ob sessions works great). You can do this while in the presence of people but do not force her to meet them.