I don't know if you're male or female, but there are some studies that show zinc supplements in both men and women and folic acid supplements in women improve mood. Both are fairly safe if taken in the suggested amount and don't interact with a whole lot. I personally also take a good multivitamin and a B complex. B vitamins theoretically improve energy and they're water soluble, so any excess, you just pee out.
Be careful with many of the "natural" supplements, as a previous poster suggested, especially St. Johns wort, Kava kava, and many others.
Personally, I think if your meds are working, that's great and I'd consider myself blessed.
For me, exercise, eating well, good relationships, therapy, a good relationship with my doctor and a sun lamp have also been beneficial.
I think it takes a village.