Pythons are no big concern: Not even venomous. They can be nasty but generally only eat stuff like cats. Eastern Diamondbacks, on the other hand can be lethal. And they are already well-established throughout Florida and Georgia. I read one story about a herpetologist who got bitten out on an island in central Florida. He had to use his boat to get to shore, and then he could barely crawl to his car to drive somewhere he could get help.

Rattlers around here give you plenty of time to get to a hospital, assuming you aren't hiking out of cell phone range of 911.