We have more room & more existing diversity - but less planning! So, great topic (even though I thought it was going to be about how to keep the farm in the family... that kind of succession, which is more daunting, even depressing, so I like dwelling on this idea better!).
Mainly the family farm is cattle and hay. But our piece of it has cleared land (currently a lot of lawn) as well as the bull pasture. Technically I get to decide all of the planting stuff, but practically we have requirements that are fixed, such as places I can't plant anything (because that's where the trailer needs to go when we're moving bulls, for example). Indeed a lot of the property is set aside for one reason or another, and we have giant white oaks that cast shade over much of the rest. Maybe I have an acre? But also wooded acreage around the edges. As we move toward retirement from both day jobs, we've done a fair amount of revisions to meet varying needs, and frankly just this year I'm starting to see something like a strategy emerging.
1. Medicinal, herbal, useful, sustainable.
Besides not-very-serious veg farming, this is the original foundation of our approach. First, things that meet our own health and welfare needs, with about a decade now learning what will grow easily or not, and establishing areas for this and that, especially focusing on perennials and root-harvest things that need time to sustainable harvest. We have this and that all over.
2. Two gardens.
The upper garden we built first. Because of deer, groundhogs, and assorted other felonious beasts, it's fortified with 9-10' fencing of three to five types: "rabbit" type down low, then alternating barbed wire and electrified, with reinforcements in a few vulnerable places. Then we added a lower garden on the other side of the bull pasture, but I'm still broadforking that one into submission. The upper garden gets planted every summer, rotating sections with our favorite stuff, and last fall I used a section for winter garlic, while the lower garden so far has been more experimental. Each one is about 15x25'.
3. Trees berries guilds and forest.
We started with a few apple, plum, and pear trees from big box stores and suboptimally situated. Then I got interested. Now we have heritage apples all around, mulberries, and a wide variety of other berry/fruit/other productive patches in the open areas and edging all of the woods. We also have black walnuts (their own special opportunity and challenge!) and pecans. I'm now encroaching into the woods with my schemes, but all of this is far less developed, mostly unplanned and evolving as we go. Some of this is medicinal, as well.
So that's the big picture! It's kind of sprawly and a ton of work, but I can hardly wait to retire and enjoy the process full time. Hope this may spark some ideas for a few others.