foofanella,
Vero sounds like a great option for X-mas. December weather in Central Florida should not be an issue. Our "coldest" days are generally late January and February. December days in the upper 70's low 80's are not uncommon but even the 60's with the sun shining is not bad. I personally would not hesitate to book a Vero reservation in December and have any concerns about the weather. Good Luck!
Scot D.