Yaupon Holly(for caffeine), firethorn, muscadine grapes, garden huckleberry (S. nigrum), various bramble berries, sparkleberry (blueberry relative in which some are not astringent but are a bit grainy but not bad), and elderberry are some more I thought of now.
Everglades tomato and Seminole pumpkin as mentioned above are fantastic producers and are very prolific in every way here in Florida. Highly recommend them regardless if they are truly native or not. Also highly recommend Chickasaw plum. I grow Chickasaw plum and some wild ones grow decent flavored and sized fruit naturally. Not sure about the flat woods plum however there's a really small plum variety I've found that's tart but would be great for jellies etc. Happen to have seeds stratifying right now for that.