Sometimes, you find that you just need to look at things a little differently or that you need to search a little harder for the right variety. For example, palmetto can be used as heart of palm and is as good as any I have ever tasted. Why not keep it as part of the food forest system by selectively harvesting and eating it?
Also, don't buy into the idea that a food forest is not any work. My perspective on 9b has always been that we can grow anything as long as we are willing to put in the work to grow it. One of the biggest flaws in food forest designs in my opinion (even among big name youtubers) is not providing or maintaining enough light for good fruit production.
Fruits native to your part of the state include, Florida paw paws, persimmon, muscadine grapes, blackberry, blueberry, plum, hickory, maypop passion fruit and mulberry. Many of these can be used as rootstocks for improved varieties. I would encourage you to try Asian persimmon (on american roots), Scarlet Beauty Plum (on native plum roots), Ison, Supreme, and other muscadine grapes, Lake Emerald and Tari's Burgundy are bunch type grapes that make nice juice, Pakistani or other improved mulberry (some may need grafting), Loquat should also do well for you if it gets good drainage, peruvian apple and opuntia cactus are more cold hardy than Dragon fruit and might do better in your location. Some kinds of avocado will also fruit in your zone. Finally, if you have a place that gets full sun, sugarcane would be a great addition. Just make sure to get a cane juicer (see thread on this forum).
I have tons of palmetto scrub, quite literally. Even clearing this area will barely make a dent. Unfortunately palmetto strips the hell out of the soil leaving almost white grey sand compared to the darker grey sand out of the palmetto stands. So there is a lot of work to do to improve the soil which will take years. After walking around yesterday in the light drizzle I will be clearing an area of about 3000 square feet this year to get that going.
Many of your suggested trees are already on the menu. I'll look into the two cacti-types you mentioned. I have about 4 or 5 loquats already on property, they take forever to grow and fruit, even the grafted varieties. Really anxious to try the persimmons again. I havent had much luck in the past with them but I know the late Bob from Green Jungle had several really nice ones in ground at his nursery.
Cattley (strawberry or lemon) guava and White sappote might do ok, too.
I have lemon already and I keep it but am not a big fan. I think the texture is kind of gross. My white sapote is about 7 years old and wasnt growing for years until I started removing those snakehead caterpillars that kept destroying all the leaves. Its grown quite a bit since but no fruit as of yet.
I am not new at fruit trees. I have an existing 2 acre yard with around 80ish trees of everything from mango, pecan and olive to star fruit, 9 pound lemon, and banana. This is more set up widely spaced orchard style instead of the more close knit style of a food forest which I am trying to do on the new property. Mostly to see if I can get better productivity at a higher density out of the same crap soil. I was also planning on trying quite a few flowering trees for looks and attracting pollinators.
I'll have a look at the mango person and the fruit geek guy.