I think that elements of Welty's fundamental view of life which can be taken from the story is the presence of struggle in one's existence.  Certainly, Welty understood this in her own condition of being as one in which the need to overcome struggle is evident.  Welty grew up in the Great Depression, where struggle was everywhere.  She also sought to be a working woman, another realm in which struggle is displayed.  Phoenix Jackson's journey is one undertaken with the presence of struggle understood.  The thorns, the obstacles of the dog and hunter, the callousness of people around her will not prevent her from doing her job.  

At the same time, one can see how Welty's desire to write and to compose thoughts about her world of the South was something that drove her and animated her.  She was so closely identified with what she loved.  For Welty, her view of life can be seen as that one is what they love.  Phoenix is much the same way.  She clearly understands that her grandson needs her and she makes the dangerous trek, fighting all the elements that present themselves, because of this love.  For Phoenix, she is what she loves.  Phoenix is the love embodied for her grandson and the devotion she feels for him.  In both of these, one sees Welty's view of life represented in the story.  Life as being defined by challenges that need to be faced and overcome as well as individuals representing what it is they love are both critical elements that define Phoenix as well as Welty's understanding of life.