Lamictal did not work out that well for me. However, I know many others who think it is a really good mood stabilizer with very good antidepressant properties. This may be part of the reason why you are not on an antidepressant. Zyprexa made me gain a lot of weight fast and I stopped it quickly.
I haven't been on Mirapex or Metformin, though there are others on the forums who take Metformin. My doctor discussed putting me on Mirapex which is for Parkinson's disease when I had a lot of Parkinsonian side effects like akathisia which were caused by antipsychotics I was taking. I didn't try it, because it seemed to have plenty of side effects itself.