Linda
You have obviously been researching this for some time, the current planning stage as LEOOEL mentioned is important, its like a mental time travel, looking ahead and imagining how everything will look, years from now.
questions to ask yourself when "designing" these systems, is, will there be enough water during the dry season, where will the water flow during a storm? are there measures to prevent erosion?, will you have a pond? animals? what about the nutrients for the plants?
Most of the projects I have seen of reclaiming land to make a food forest usually starts off by preparing the land some how, with swales, then adding some nitrogen short term ground covers to build soil fertility. then adding misc trees and shrubs, in certain ratios, but typically at first, you may only have 10% fruiting trees to 90% service trees, which over time gradually is reduced and more and more fruiting trees are added. the end ratio I believe depends on the environmental factors, but the idea is to be self sustaining where no outside nutrients are needed. If I am not mistaken I think that is your intention.
Service trees build the soil, both from the leaves they drop, but also when you coppice them, by being pro active, you are speeding up the natural process. in a few years, even the nastiest soils can be fertile again. of course if your soils are not that bad, a different strategy can be taken. and less time will be needed to build the soils up before many fruit trees go in. but its still important that you have support trees that will be able to "feed" your fruit trees.
I think animals can be useful here, even if you do not consume the animals, a small pond can supply lots of fish, Tilapia grow fast, and are a good source of protein. in and around the pond, you can have plants that like marshes, for example Lotus grow in the water, are beautiful, but the seeds and roots are edible, some are medicinal. the location of the pond can help regulate temperatures, the reflected light used to keep some areas warmer.
Ducks can keep some pest in control, like snails. duckweed in the pond is another source of food for the ducks. the duckweed gets its nutrients from the pond from the tilapia waste.
Fungi in my opinion is very important, inoculating with many different types of beneficial fungi will benefit the whole system.
Pages could be written on all the things you can do, and plants that can be used. for example, Comfrey, is a wonderful medicinal, that also makes a great natural fertilizer, as it brings up minerals from deep in the ground. vetivar grass is good for creating borders and preventing erosion, just make sure you use non spreading versions of these plants.