I faced that same question; I had just finished my BSN by scholarship, no student loan dept, happy graduation, feeling on top of the world and could do anything. So I considered - should I just go for the MD or Psychiatrist?
I came to the conclusion that no, I liked the nursing approach. I looked around and there are enough states where the NP's have prescriptive privledges and independent practice, so I can find a place where I can practice as I like. I don't like the medical model of care; I like the multifaceted nursing approach (I summarize it as: Physical, Cognitive, Emotional, Spiritual and Social) in my opinion, the average medically trained practicioner (PA, MD, DO, Psychiatrist) will miss most of the patient.
Every month I've been in school (well more like every 2-3 weeks) in my BSN-DNP program, I've gotten forwarded e-mails from the student advisors, hoping to welcome new grads into rural positions and offering nice monies. So I'll have a place to go (many) and I'll probably be able to get repayment help on my loans.
The other side of this; go back to the 1800's, just before publication of the Flexner report. There were many types of "doctors", homeopaths and chiropractics and so on. The AMA was really successful in obliterating their competition, but nature abhors a vaccumm, and there is a place for doctoral level providers who are not allopathic-trained folks. Someday that will be me.