Hi, M.!
Our pedi is in Plano at Medical Center of Plano, and I know that won't be feasible for you, especially when the kids get sick...
But I did want to make a comment about your choice of a new pediatrician. If you have developed a relationship with the PA's in the office, then you should feel "well taken care of" with that respect. (From a personal as well as professional standpoint, I stand by our PA's.)
However, your feeling of "lack of organization" and your daughter's NEVER having seen her pediatrician is certainly cause for seeking a new pediatrician are certainly grouds for seeking a new doctor. Our son sees his NP's whenever he is not feeling well, but if there is something going on that they are not sure about, they find either one of the pediatricians and ASK. For his "well baby" visits, we certainly do see our pediatrician. (Occasionally, we will see our secondary pedi, but he is older, and we are very comfortable with him, as well.)
My 2nd piece of advice is to start looking for a female adolescent doctor, especially if your daughter has only recently or has *not* started her periods yet. And make sure your first appt with the pedi/adolescent dr is to "interview" the dr. You don't want to find out during an exam that your daughter is not comfortable with the dr. examining her!
HTH!