Convert Organic to Permaculture - Advice?

I live in Central Florida, in zone 9B. It is mainly hot and humid here. We have mild dry winters and rainy hot humid summers. I own an organic Peach and Blueberry orchard. However, I found the organic system needed quite a bit of inputs and wasn't as sustainable as I had thought it would be. I removed all of the Peach trees and most of the Blueberry bushes. Therefore, I have been looking at converting to Permaculture. My biggest issue is weed suppression here. I'm thinking of using nitrogen fixing ground covers, such as perennial peanut and our native sunshine mimosa to help with nitrogen and weed suppress. I would like anyone thoughts on anything they have used and have been successful with using in there own system. Also, I'm on part of the natural sand ridge, so parts of my property is on a slope and I have one spot that has erosion issues. I would like to know how some successful swells were built and how to build them correctly. I did a short video on my property to point out the trouble spots. I appreciate any suggestions or advice. Thank you.