Melbourne Beach is surprisingly warm, but you have to beware wind resistance.

Here's a tree list by Eric of Leu Gardens in Orlando from a discussion at Palm Talk:

Peltophorum dubium is hardy into the mid 20s, low 20s with damage. They are fast growing, drought tolerant, and fairly wind resistant but can get some size. I wouldn't plant one where that oak is now, should give one more room away from the house.

Magnolia (Michelia) chamapa (roange) and x alba are good in the warmer parts of central FL and into south FL but need acidic soil. They tolerate to 29-30F with no real damage. Some around town in cold spots suffered damage the past 2 winters, mostly burnt leaves/twig dieback. They probably saw 27-29F and heavy frost. Colder than that will start to inflict more serious damage.

So good choices;

Quercus geminata- Sand Live Oak, evergreen native, like a dwarf Q. virginiana, 20-25 ft.

Aloysia virgata- Sweet Almond Bush- actually grows as a tree 10-20ft.
Bauhinia forficata- Thorny Orchid Tree
Bougainvillea arborea
Caesalpinia mexicana- Mexican Poinciana
Cassia leptophylla- Gold Medallion Tree
Cordia boissieri- Anacahuita or Wild Olive, very drought tolerant, flowers on and off all year
Ebenopsis ebano- Texas Ebony (Pithecellobium flexicaule)
Elaeocarpus decipiens- Asian Blueberry Tree
Handroanthus chrysotrichus- Golden Trumpet tree (formerly Tabebuia chrysotricha)
Handroanthus heptaphyllus- Purple Trumpet tree (formerly Tabebuia heptaphylla)- flowers in fall
Handroanthus impetiginosus- Pink Trumpet tree (formerly Tabebuia impetiginosa)
Handroanthus umbellatus- Yellow Trumpet tree (formerly Tabebuia umbellata)
Nageia nagi (formerly Podocarpus)-Nagi or Broadleaf Podocarpus the most wind resistant tree we had through the hurricanes

Neolitsea sericea- Japanese Silver Tree
Taxodium ascendens- Pond Cypress

Most of these are hard to obtain.

Some of the larger crape myrtles are truly tree-sized, and they are very wind resistant.  Muskogee and Natchez are easy to find.  IFAS