Since this will be your first winter you might want to check out a couple of areas. Depending upon which months you plan to be in Florida you could consider further south in January (say 50+ miles south of I-4) then moving a bit further north in February (maybe 20-40 miles north or south of I-4) and then in March you might consider areas about 50-80 miles north of Tampa/Orlando.
Our first year snowbirding, 2013, we stayed in about 8 or 9 different campgrounds from north to south to back north. We first stayed in Crystal River (north Gulf Coast) moved to Osprey (Sarasota area) to Marathon in the Keys to just north of Homestead (Miami area) to Sebring to Winter Haven to Umatilla (NW of Orlando) and then back to Crystal River. We decided we didn't mind it a bit cooler and have stayed in Crystal River much of our January-March the past 2 winters and have signed up for 3 full months at Rock Crusher Canyon RV Park again for 2016.
Crystal River (the Nature Coast) is more rural than further south and has much less traffic (not much in the way of beaches). There were several nights in the 30's in January and February, but the days usually warmed up into the 60's and sometimes into the low 70's. It was a cooler winter in February almost everywhere in the upper 3/4's of Florida. March was quite warm in Crystal River with the last 3 weeks of the month mostly in the 80's.
Experience a bit of south-central-north and maybe a little east coast/west coast. That first year we moved every 3-7 days which is a bit much, but we only went for about 6 weeks. We did get to see different parks and areas which can be fun if you like that sort of thing. It's ok to some extent, but it's also a lot of fun to stay in one park so you can better get to know other snowbirders, participate in regular activities, and become more familiar with the general area.
You're in control of the agenda. Enjoy it!
