I have a property in west broward, water table varies from 1-3 feet below ground surface throughout year. I also have nearly 100% muck on limerock, no sand, so high ability to hold water. I have some stuff on 1-2 ft mounds, but I honestly doubt it make any difference. This is my experience with trees in the ground:
Do well: custard apple, banana, mango, longan, peanut butter fruit, acerola, jamaican cherry, sapodilla, surinam cherry(flowering/fruiting not very good, but leaf growth is amazing), avacado ( i know people say this doesn't like wet feet, but me and many neighbors have amazing looking avocado trees), pineapple, guava
Do terrible: sugar apple, atemoya, star fruit, lychee, loquat, mamey sapote, jackfruit, white sapote
Do you have a high water table or do you have poor draining soil? Both these issues can be alleviated by not having monoculture lawn around your trees that you mow, because this situation creates compaction and flooding. More diversity of roots will help with drainage by increasing aeration through better soil structure and more macro pores.